Exchange Server prerequisites

This topic provides the steps for installing the necessary Windows Server operating system prerequisites for Exchange Server 2016 and Exchange Server 2019 Mailbox servers and Edge Transport servers, and also the Windows prerequisites for installing the Exchange Management Tools on Windows client computers.

After you’ve prepared your environment for Exchange Server, use the Exchange Deployment Assistant for the next steps in your actual deployment. For information on hybrid deployments, see Exchange Server Hybrid Deployments.

To actually install Exchange 2016 and Exchange 2019, see Deploy new installations of Exchange.

Looking for Exchange 2013 prerequisites? See Exchange 2013 prerequisites.

Remote Registry Service must be set to Automatic and cannot be Disabled. For recommended Security Guidelines, See Security Guidelines regarding Remote Registry.

Have you heard about the Exchange Server Deployment Assistant? It’s a free online tool that helps you quickly deploy Exchange Server in your organization by asking you a few questions and creating a customized deployment checklist just for you. If you want to learn more about it, go to Microsoft Exchange Server Deployment Assistant.

What do you need to know before you begin?

• Verify that your Active Directory meets the requirements for Exchange 2019: Exchange 2019 Network and directory servers.

Verify that your Active Directory meets the requirements for Exchange 2016: Exchange 2016 Network and directory servers.

The full installation option of Windows Server 2012 and Windows Server 2012 R2 must be used for all servers running Exchange 2016 server roles or management tools.

Some prerequisites require you to reboot the server to complete installation.

You can’t upgrade Windows from one version to another, or from Standard to Datacenter, when Exchange is installed on the server.

New to Exchange 2019 is the ability to upgrade your operating system to a newer version while Exchange is installed on Windows Server 2019 or later.

Verify the computer is joined to the appropriate internal Active Directory domain.

Install the latest Windows updates on your computer.

Having problems? Ask for help in the Exchange forums. Visit the forums at: Exchange Server.

Exchange 2019 prerequisites for preparing Active Directory

You can use any member of the Active Directory domain to prepare Active Directory for Exchange 2019.

The computer requires the following software:

• When installing on Windows Server Core, you must use key «/q» for install this package. Optionaly you can use «/log [PATH]» for logging.

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

The Visual C++ Redistributable package is required if you’re using the Exchange Setup Wizard to prepare Active Directory. If you’re using unattended Setup from the command line to prepare Active Directory, this package isn’t required. For more information, see Prepare Active Directory and domains.

Install the Remote Tools Administration Pack by running the following command in Windows PowerShell:

Using the Exchange Setup Wizard to prepare Active Directory requires the installation of the Management Tools Exchange role.

Windows Server 2019 prerequisites for Exchange 2019

The requirements to install Exchange 2019 on Windows Server 2019 computers are described in the following sections. We recommend either of the following methods to install the Windows prerequisites for Exchange 2019:

Use the /InstallWindowsComponents switch in unattended Setup mode.

Select the check box in the Exchange Setup Wizard to install Windows prerequisites.

When you use one of these options, you don’t need to restart the computer after the Windows components have been added.

Exchange 2019 Mailbox servers on Windows Server 2019

Install the following software:

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions

Add the required Lync Server or Skype for Business Server components:

a. Install the Server Media Foundation windows feature by executing the following command in Windows PowerShell:

b. Install Unified Communications Managed API 4.0. This package is available for download and in the \UCMARedist folder on the Exchange Server media.

When installing on Windows Server Core, you must use the installation package located in \UCMARedist on distributed media.

If you aren’t going to use Exchange Setup to install the required Windows components (in the wizard or from the command line), run the one of the following commands in Windows PowerShell:

Desktop Experience:

Server Core:

Exchange 2019 Edge Transport servers on Windows Server 2019

Install the following software:

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

If you aren’t going to use Exchange Setup to install the required Windows components (in the wizard or from the command line), run the following command in Windows PowerShell:

Windows 10 client prerequisites for the Exchange 2019 management tools

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

If you aren’t going to use Exchange Setup to install the required Windows components (in the wizard or from the command line), run the following command in Windows PowerShell:

Exchange 2016 prerequisites for preparing Active Directory

You can use any member of the Active Directory domain to prepare Active Directory for Exchange 2016.

The computer requires the following software:

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

Install the Remote Tools Administration Pack by running the following command in Windows PowerShell:

After you’ve installed the Remote Tools Administration Pack you can use the computer to prepare Active Directory. For more information, see Prepare Active Directory and domains.

Windows Server 2016 prerequisites for Exchange 2016

The prerequisites that are needed to install Exchange 2016 on computers running Windows Server 2016 depends on which Exchange role you want to install. Read the section below that matches the role you want to install.

Windows Server 2016 requires Exchange 2016 Cumulative Update 3 or later.

Exchange 2016 Mailbox servers on Windows Server 2016

Run the following command in Windows PowerShell to install the required Windows components:

Install the following software in order:

You can only install this update if your Windows Server 2016 version is 14393.576 or earlier (circa December, 2016). You can check your Windows Server version by running the winver command. If your Windows Server 2016 version is greater than 14393.576, you don’t need this update or its replacement KB3213522, which was released one week later. Exchange 2016 Setup looks for the installation of this update, won’t allow you to continue if this update is missing, and will clearly inform you if you need it.

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

Only the Mailbox role requires the Visual C++ Redistributable Packages for Visual Studio 2013. Other Exchange installations (management tools and Edge Transport) only require the Visual C++ Redistributable Packages for Visual Studio 2012.

Exchange 2016 Edge Transport servers on Windows Server 2016

Run the following command in Windows PowerShell to install the required Windows components:

Install the following software in order:

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

Windows Server 2012 and Windows Server 2012 R2 prerequisites for Exchange 2016

The prerequisites for Exchange 2016 on Windows Server 2012 or Windows Server 2012 R2 computers depend on the Exchange role that you’re installing. Read the following section that matches the role you want to install.

Exchange 2016 Mailbox servers on Windows Server 2012 or Windows Server 2012 R2

Run the following command in Windows Powershell to install the required Windows components:

Install the following software in order:

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

Only the Mailbox role requires the Visual C++ Redistributable Packages for Visual Studio 2013. Installations of the Exchange management tools and Edge Transport servers only require the Visual C++ Redistributable Packages for Visual Studio 2012.

Exchange 2016 Edge Transport servers on Windows Server 2012 or Windows Server 2012 R2

Run the following command in Windows PowerShell to install the required Windows components:

Install the following software in order:

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

Windows client prerequisites for the Exchange 2016 management tools

Exchange 2016 management tools on Windows 10

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

Run the following command in an elevated Windows PowerShell window (a Windows PowerShell window you open by selecting Run as administrator):

Exchange 2016 management tools on Windows 8.1

The system requirements for the Visual C++ redistributable package do not mention support for Windows Server 2016 or Windows Server 2019, but the redistributable package is safe to install on these versions of Windows.

An overview of the latest supported versions is available at: Visual C++ Redistributable versions.

Run the following command in an elevated Windows PowerShell window (a Windows PowerShell window you open by selecting Run as administrator):

Exchange Server system requirements

Before you install Exchange Server 2019, we recommend that you review this topic to ensure your network, hardware, software, clients, and other elements meet the requirements for Exchange 2019. Also, make sure you understand the coexistence scenarios that are supported for Exchange 2019 and earlier versions of Exchange.

To actually install Exchange 2019, see Deploy new installations of Exchange.

Supported coexistence scenarios for Exchange 2019

The supported coexistence scenarios between Exchange 2019 and earlier versions of Exchange are described in the following table:

Exchange version	Exchange 2019 organization coexistence
Exchange 2010 and earlier versions	Not supported
Exchange 2013	Supported with Exchange 2013 Cumulative Update 21 (CU21) or later on all Exchange 2013 servers in the organization, including Edge Transport servers.
Exchange 2016	Supported with Exchange 2016 CU11 or later on all Exchange 2016 servers in the organization, including Edge Transport servers.
Mixed Exchange 2013 and Exchange 2016 organization	Supported if all Exchange 2013 and Exchange 2016 servers in the organization meet the requirements as previously described in this table.

Supported hybrid deployment scenarios for Exchange 2019

Exchange 2019 supports hybrid deployments with Microsoft 365 or Office 365 organizations that have been upgraded to the latest version of Microsoft 365 or Office 365. For more information about specific hybrid deployments, see Hybrid deployment prerequisites.

Network and directory server requirements for Exchange 2019

The requirements for the network and the directory servers in your Exchange 2019 organization are described in the following table:

Component	Requirement
Domain controllers	All domain controllers in the forest need to be running one of the following versions of Windows Server: Windows Server 2019 Standard or Datacenter Windows Server 2016 Standard or Datacenter Windows Server 2012 R2 Standard or Datacenter
Active Directory forest	The Active Directory forest functional level is Windows Server 2012 R2 or higher.
Active Directory site	The Active Directory site where you install the Exchange Server must contain at least one writeable domain controller that’s also a global catalog server, or the installation will fail. Furthermore, you can’t install the Exchange server and then remove the domain controller from the Active Directory site.
DNS namespace	Exchange 2019 supports the following DNS namespaces: Contiguous Noncontiguous Single label domains Disjoint For more information about DNS namespaces that are supported by Exchange, see KB2269838.
IPv6	Exchange 2013 and later support IPv6 only when IPv4 is also installed and enabled on the Exchange server. If you deploy Exchange in this configuration, and your network supports IPv4 and IPv6, all Exchange servers can send data to and receive data from devices, servers, and clients that use IPv6 addresses. For more information, see IPv6 Support in Exchange 2013.

Directory server architecture for Exchange 2019

Active Directory domain controllers on 64-bit hardware with a 64-bit version of Windows Server will increase directory service performance for Exchange 2019.

Installing Exchange 2019 on directory servers

For security and performance reasons, we don’t recommend installing Exchange 2019 on Active Directory directory servers. Only install Exchange 2019 on member servers.

To learn more about the issues that you’ll encounter when you install Exchange on a directory server, see Installing Exchange on a domain controller is not recommended [WarningInstallExchangeRolesOnDomainController]. After Exchange is installed, changing the server role from a member server to a directory server or vice-versa isn’t supported.

Hardware requirements for Exchange 2019

For information about deploying Exchange in a virtualized environment, see Exchange Server virtualization.

Component	Requirement	Notes
Processor	Either of the following types of 64-bit processors: Intel processor that supports Intel 64 architecture (formerly known as Intel EM64T). AMD processor that supports the AMD64 platform. Notes: Intel Itanium IA64 processors are not supported. Recommended supported processor sockets is up to 2 on physical machines.	See the Supported operating systems for Exchange 2019 section later in this topic for supported operating systems.
Memory	Varies by Exchange server role: Mailbox: 128 GB minimum recommended Edge Transport: 64 GB minimum recommended.	Exchange 2019 has large memory support (up to 256 GB).
Paging file size	Set the paging file minimum and maximum value to the same size: 25% of installed memory.	None
Disk space	At least 30 GB of free space on the drive where you’re installing Exchange. At least 200 MB of free space on the system drive. At least 500 MB of free space on the drive that contains the message queue database.	None
Screen resolution	1024 x 768 pixels (XGA) or higher	None
File system	NTFS: Required on partitions that contain the following types of files: The System partition. Exchange binaries. Files generated by Exchange diagnostic logging. Transport database files (for example, the mail queue database). ReFS: Supported on partitions that contain the following types of Exchange files: Mailbox databases. Transaction logs.	None

Supported operating systems for Exchange 2019

Exchange component	Requirement
Mailbox and Edge Transport server roles	Windows Server 2019 Standard or Datacenter
Management tools	One of the following versions of Windows: Windows Server 2019 Standard or Datacenter 64-bit edition of Windows 10

Installing Exchange 2019 on a computer that’s running Windows Server Core is fully supported and recommended. The Desktop Experience feature is no longer required.

Installing Exchange 2019 on a computer that’s running Nano Server isn’t supported.

Supported PowerShell versions for Exchange 2019 servers

Exchange 2019 servers support the version of PowerShell that’s included in the release of Windows Server where Exchange is installed. Don’t install stand-alone downloads of WMF or PowerShell on Exchange servers.

Installing other software on Exchange 2019 servers

We don’t support installing Office client or Office server software on Exchange servers (for example, SharePoint Server, Skype for Business Server, Office Online Server, or Project Server). Other software that you want to install on an Exchange 2019 server needs to be designed to run on the same computer as Exchange Server.

Supported .NET Framework versions for Exchange 2019

We strongly recommend that you use the latest version of the .NET Framework that’s supported by the release of Exchange you’re installing.

Releases of .NET Framework that aren’t listed in the table below aren’t supported on any release of Exchange 2019. This includes minor and patch-level releases of .NET Framework.

The complete prerequisite list for Exchange 2019 is available here.

Exchange 2019 version	.NET Framework 4.8	.NET Framework 4.7.2
CU4 to CU9	Supported
CU2, CU3	Supported	Supported
RTM, CU1	Supported

Supported clients (with latest updates) in Exchange 2019

• Microsoft 365 Apps for enterprise
• Outlook 2019
• Outlook 2016
• Outlook 2013
• Outlook for Mac for Office 365
• Outlook 2016 for Mac

You need KB3140245 to apply registry keys to enable TLS 1.1 & 1.2 support for Windows 7. Otherwise, Outlook 2013 and 2016 will not work on Windows 7.

Lync/Skype For Business Server integration with Exchange 2019

If you’re integrating Lync presence and instant messaging with Exchange Server, Lync Server 2013 Cumulative Update 10 or later is required. If you’re integrating Skype for Business presence and instant messaging with Exchange Server, Skype for Business Server Cumulative Update 7 or later is required.

Before you install Exchange Server 2016, we recommend that you review this topic to ensure your network, hardware, software, clients, and other elements meet the requirements for Exchange 2016. Also, make sure you understand the coexistence scenarios that are supported for Exchange 2016 and earlier versions of Exchange.

To actually install Exchange 2016, see Deploy new installations of Exchange.

Supported coexistence scenarios for Exchange 2016

The following table lists the scenarios in which coexistence between Exchange 2016 and earlier versions of Exchange is supported.

Exchange version	Exchange organization coexistence
Exchange 2007 and earlier versions	Not supported
Exchange 2010	Supported with Update Rollup 11 for Exchange 2010 SP3 or later on all Exchange 2010 servers in the organization, including Edge Transport servers.
Exchange 2013	Supported with Exchange 2013 Cumulative Update 10 or later on all Exchange 2013 servers in the organization, including Edge Transport servers.
Mixed Exchange 2010 and Exchange 2013 organization	Supported with the following minimum versions of Exchange: Update Rollup 11 Exchange 2010 SP3 or later on all Exchange 2010 servers in the organization, including Edge Transport servers. Exchange 2013 Cumulative Update 10 or later on all Exchange 2013 servers in the organization, including Edge Transport servers.

Supported hybrid deployment scenarios for Exchange 2016

Exchange 2016 supports hybrid deployments with Microsoft 365 or Office 365 organizations that have been upgraded to the latest version of Microsoft 365 or Office 365. For more information about specific hybrid deployments, see Hybrid Deployment Prerequisites.

Network and directory server requirements for Exchange 2016

The following table lists the requirements for the network and the directory servers in your Exchange 2016 organization.

Component	Requirement
Domain controllers	All domain controllers in the forest need to be running one of the following versions of Windows Server: Windows Server 2019 Standard or Datacenter Windows Server 2016 Standard or Datacenter Windows Server 2012 R2 Standard or Datacenter Windows Server 2012 Standard or Datacenter Windows Server 2008 R2 Standard or Enterprise Windows Server 2008 R2 Datacenter RTM or later
Active Directory forest	The Active Directory forest functional level is Windows Server 2008 R2 or higher.
Active Directory site	The Active Directory site where you install the Exchange Server must contain at least one writeable domain controller that’s also a global catalog server, or the installation will fail. Furthermore, you can’t install the Exchange server and then remove the domain controller from the Active Directory site.
DNS namespace support	Exchange 2016 supports the following domain name system (DNS) namespaces: Contiguous Noncontiguous Single label domains Disjoint For more information about DNS namespaces supported by Exchange, see Microsoft Knowledge Base article 2269838, Microsoft Exchange compatibility with Single Label Domains, Disjoined Namespaces, and Discontiguous Namespaces.
IPv6 support	In Exchange 2016, IPv6 is supported only when IPv4 is also installed and enabled. If Exchange 2016 is deployed in this configuration, and the network supports IPv4 and IPv6, all Exchange servers can send data to and receive data from devices, servers, and clients that use IPv6 addresses. For more information, see IPv6 Support in Exchange 2013.

Directory server architecture for Exchange 2016

The use of 64-bit Active Directory domain controllers increases directory service performance for Exchange 2016.

In multi-domain environments, on Windows Server 2008 domain controllers that have the Active Directory language locale set to Japanese (ja-jp), your servers may not receive some attributes that are stored on an object during inbound replication. For more information, see KB949189.

Installing Exchange 2016 on directory servers

For security and performance reasons, we recommend that you install Exchange 2016 only on member servers and not on Active Directory directory servers. To learn about the issues you can face when installing Exchange 2016 on a directory server, see Installing Exchange on a domain controller is not recommended [WarningInstallExchangeRolesOnDomainController]. After Exchange 2016 is installed, changing its role from a member server to a directory server, or vice versa, isn’t supported.

Hardware requirements for Exchange 2016

For information about deploying Exchange in a virtualized environment, see Exchange Server virtualization.

Component	Requirement	Notes
Processor	Either of the following types of 64-bit processors: Intel processor that supports Intel 64 architecture (formerly known as Intel EM64T). AMD processor that supports the AMD64 platform. Note: Intel Itanium IA64 processors are not supported.	For more information, see Sizing Exchange 2016 Deployments. See the Supported operating systems for Exchange 2016 section later in this topic for supported operating systems.
Memory	Varies by Exchange server role: Mailbox: 8 GB minimum. Edge Transport: 4 GB minimum.	For more information, see Sizing Exchange 2016 Deployments.
Paging file size	Set the paging file minimum and maximum value to the same size: Less than 32 GB of RAM installed: Physical RAM plus 10 MB, up to a maximum value of 32 GB (32,778MB). 32 GB of RAM or more installed: 32 GB plus 10 MB (32,778MB)	None
Disk space	At least 30 GB of free space on the drive where you’re installing Exchange, plus an additional 500 MB for each Unified Messaging (UM) language pack that you plan to install. At least 200 MB of free space on the System drive. At least 500 MB of free space on the drive that contains the message queue database.	For more information, see Sizing Exchange 2016 Deployments.
Drive	DVD-ROM drive, local or network accessible.	None
Screen resolution	1024 x 768 pixels (XGA) or higher	None
File format	NTFS: Required on partitions that contain the following types of files: The System partition. Exchange binaries. Files generated by Exchange diagnostic logging. Transport database files (for example, the mail queue database). ReFS: Supported on partitions that contain the following types of Exchange files: Mailbox databases. Transaction logs. Content indexing files.	None

Supported operating systems for Exchange 2016

Important: We don’t support the installation of Exchange 2016 on a computer that’s running Windows Server Core or Nano Server. The Windows Server Desktop Experience feature needs to be installed. To install Exchange 2016, you need to do one of the following steps to install the Desktop Experience on Windows Server prior to starting Exchange 2016 Setup:

Windows Server 2012 and Windows Server 2012 R2: Run the following command in Windows PowerShell

Windows Server 2016: Install Windows Server 2016 and choose the Desktop Experience installation option. If a computer is running Windows Server 2016 Core mode and you want to install Exchange 2016 on it, you’ll need to reinstall the operating system and choose the Desktop Experience installation option.

Component	Requirement
Mailbox and Edge Transport server roles	Windows Server 2016 Standard or Datacenter * Windows Server 2012 R2 Standard or Datacenter Windows Server 2012 Standard or Datacenter
Management tools	One of the following versions of Windows: Windows Server 2016 Standard or Datacenter * Windows Server 2012 R2 Standard or Datacenter Windows Server 2012 Standard or Datacenter 64-bit edition of Windows 10 64-bit edition of Windows 8.1

* Requires Exchange Server 2016 Cumulative Update 3 or later.

Supported Windows Management Framework versions for Exchange 2016

Exchange 2016 only supports the version of Windows Management Framework that’s built in to the release of Windows that you’re installing Exchange on. Don’t install versions of Windows Management Framework that are made available as stand-alone downloads on servers running Exchange.

Installing other software on Exchange 2016 servers

We don’t support installing Office clients or other Office server products (for example, SharePoint Server, Skype for Business Server, Office Online Server, or Project Server) on Exchange 2016 servers. Software that you want to install on an Exchange 2016 server needs to be designed to run on the same computer as Exchange Server.

Supported .NET Framework versions for Exchange 2016

We strongly recommend that you use the latest version of .NET Framework that’s supported by the release of Exchange you’re installing.

Releases of .NET Framework that aren’t listed in the table below are not supported on any release of Exchange 2016. This includes minor and patch-level releases of .NET Framework.

The complete prerequisite list for Exchange 2016 is available here.

Exchange 2016 version	.NET Framework 4.8	.NET Framework 4.7.2	.NET Framework 4.7.1	.NET Framework 4.6.2
CU15 to CU20	Supported
CU13, CU14	Supported	Supported
CU11, CU12	Supported	Supported
CU10	Supported
CU8, CU9	Supported	Supported
CU5, CU6, CU7	Supported

Supported clients (with latest updates) in Exchange 2016

• Microsoft 365 Apps for enterprise
• Outlook 2019
• Outlook 2016
• Outlook 2013
• Outlook 2010 SP2
• Outlook 2016 for Mac
• Outlook for Mac for Office 365

Exchange third-party clients

Exchange Server offers several well-known protocols, and publishes APIs that third-party vendors often write clients for.

Microsoft makes no warranties, expressed or implied, as to the overall suitability, fitness, compatibility, or security of clients that are created by third-party developers.

If you want to use a third-party client that uses our protocols or APIs, we recommend that you thoroughly review and test all considerations (functionality, security, maintenance, management, and so on) before you deploy the client in the enterprise workspace. We also recommend that you make sure that the third-party vendor offers an appropriate Enterprise Support Agreement (ESA).