Get help with Windows 10 upgrade and installation errors

There are many reasons why you might receive an error message when upgrading or installing Windows 10, but common errors can be fixed with a few steps that you can do on your own. Note: An upgrade takes your device from an older version of Windows, such as Windows 7 or Windows 8.1, to Windows 10.

Before searching for a specific error code, try the tips listed in General fixes. If those don’t fix your upgrade or installation problem, check the table of error codes at the bottom of this article.

General fixes

Here are some things you can try to fix upgrade and installation errors:

Unplug any nonessential hardware devices. These could include headphones, printers, scanners speakers, USB flash drives, and external hard drives.

If you’re using a laptop and it’s plugged in to a docking station, undock it.

It’s a good idea to make sure that all important updates are installed before trying to upgrade Windows. This includes updates to hardware drivers on your device.

For information and to make sure you’re up-to-date, see Windows Update: FAQ.

Use Windows Defender to protect your device during the upgrade—non-Microsoft antivirus software can sometimes cause upgrade problems. As long as you have installation media and all required activation information, you can always reinstall the software after you upgrade.

To remove an antivirus application, go to Control Panel\Programs\Programs and Features. Select the program, and then select Uninstall. Select Yes to confirm.

Outdated software can cause problems with a Windows upgrade, so removing old or nonessential applications can help.

If you plan to reinstall the application later, make sure you have the installation media and all required activation information before removing it.

To uninstall software, go to Control Panel\Programs\Programs and Features. Select the program, and then select Uninstall. Select Yes to confirm.

To upgrade to Windows 10, you need enough space on your hard drive for the installation to take place.

To view how much hard drive space is available on your computer, select the Start button, then in the search box on the taskbar, type File Explorer (known as Windows Explorer in Windows 7).

Then select Computer or This PC and look under Hard Disk Drives or under Devices and drives. If there are multiple drives listed, the system drive is the drive that includes a Microsoft Windows logo above the drive icon. You’ll see the amount of available space under the drive.

If it looks like your drive is running low on space, see Tips to free up drive space on your PC.

0xC1900101 Errors

An error that begins with 0xC1900101 is usually a driver error. If you see any of these error codes, try the following steps first to fix the problem. If these steps don’t work, see Resolve Windows 10 upgrade errors for more detailed technical info.

Make sure that your device has enough space. Your device requires at least 16 GB of free space to upgrade a 32-bit OS, or 20 GB for a 64-bit OS. For more info, see Free up drive space in Windows 10.

Run Windows Update a few times. Download and install any available updates in Windows Update, including software updates, hardware updates, and some third-party drivers. Use the troubleshooter for Windows 10 to fix Windows Update errors.

Check third-party drivers and download any updates. You can find third-party drivers and installation instructions for any hardware you’ve added to your device on the manufacturer’s website.

Unplug extra hardware. Remove all external storage devices and drives, docks, and other hardware you might have plugged into your device that isn’t needed for basic functionality.

Check Device Manager for errors. Select the Start button, then in the search box on the taskbar, type device manager. Choose Device Manager from the results. In the window that pops up, look for any device with a yellow exclamation mark beside it (you may have to select each category to switch to the list of devices). Press and hold (or right-click) the device name and select either Update Driver Software or Uninstall to correct the errors.

Remove third-party security software. Make sure you know how to reinstall your programs and that any necessary product keys are on hand. Windows Defender will help protect your device in the meantime.

Repair hard-drive errors. Select the Start button, then in the search box on the taskbar, type command prompt. Choose Command Prompt from the list of results. In the window that pops up, type chkdsk/f C: and press the Enter key. Repairs automatically start on your hard drive, and you’ll be asked to restart your device.

Note: You must have administrator permissions on your device to do this.

Do a clean restart into Windows. Learn how.

Restore and repair system files. Select the Start button, then in the search box on the taskbar, type command prompt. Choose Command Prompt from the list of results. In the window that pops up, type DISM.exe /Online /Cleanup-image /Restorehealth and press the Enter key. (Learn to repair a Windows image)

Note: You must have administrator permissions on your device to do this.

Other Common Errors

The following table lists the most common upgrade and installation errors and some things you can try to fix them. If you continue having problems upgrading or installing Windows 10, contact Microsoft support.

What it means and how to fix it

This indicates that there was a problem downloading and installing the selected update. Windows Update will try again later and there is nothing you need to do at this time.

This could indicate that an incompatible app installed on your PC is blocking the upgrade process from completing. Check to make sure that any incompatible apps are uninstalled and then try upgrading again.

A cleanup operation from a previous installation attempt is still pending, and a system restart is required to continue the upgrade. Restart the device and run setup again. If restarting device does not resolve the issue, then use the Disk Cleanup utility and clean up the temporary files and the System files. For more information, see Disk cleanup in Windows 10.

A file needed by Windows Update is likely damaged or missing. Try repairing your system files: Select the Start button and type command prompt in the search box on the taskbar. Choose Command Prompt from the list of results. In the window that appears, type DISM.exe /Online /Cleanup-image /Restorehealth and press the Enter key.

This may signify that your PC doesn’t meet the minimum requirements to download or install the upgrade to Windows 10. Learn more about the minimum requirements for Windows 10

This might indicate that a driver or other software on your PC isn’t compatible with the upgrade to Windows 10. For info about how to fix this problem, contact Microsoft support.

This could mean that the upgrade process was interrupted because you accidentally restarted your PC or signed out of your PC. Try upgrading again and make sure your PC is plugged in and stays turned on.

This error might mean that your PC couldn’t connect to the Windows Update servers. If you’re using a VPN connection to connect to a work network, disconnect from the network and turn off the VPN software (if applicable) and try upgrading again.

The error could also mean there isn’t enough free space in the System Reserved partition. You might be able to fix this problem by using third-party software to increase the size of the System Reserved partition.

Error: We couldn’t complete the updates. Undoing changes. Don’t turn off your computer.

Error: Failure configuring Windows Updates. Reverting changes.

These are generic errors that might appear any time a Windows update fails. You’ll need to determine the specific error code to investigate how to best resolve this problem.

You can find the error code for the failed update by viewing your update history. Look for the update that wasn’t installed, note the error code, and then contact Microsoft support.

To view your update history in Windows 8.1:

Open Windows Update by swiping in from the right edge of the screen (or, if you’re using a mouse, pointing to the lower-right corner of the screen and moving the mouse pointer up), select Settings > Change PC settings > Update and recovery > View your update history.

To view your update history in Windows 7:

Select the Start button. In the search box, type Update, and then, in the list of results, Select Windows Update > View update history.

Error: The update isn’t applicable to your computer.

This error might mean that your PC doesn’t have the required updates installed.

Check to make sure that all important updates are installed on your PC before you try upgrading.

This likely indicates that your PC doesn’t have enough space available to install the upgrade.

Free some space on the drive and try again. Get tips for freeing up drive space

The specified disk operation is not supported by the target disk, partition, or volume.

Make sure your machine meets the minimum requirements to install Windows 10.

The system cannot find the file specified.

If you have a disk or disks where you are not installing Windows 10 on, remove those disks.

A driver has caused a problem.

Disable or remove all 3rd party antivirus or antispyware from your system. Disconnect all peripheral devices that are connected to the system, except for the mouse, keyboard and display.

Contact your hardware vendor to obtain updated device drivers.

Windows Setup terminated unexpectedly due to another process running in the background.

When you start Windows by using a normal startup, several applications and services start automatically, and then run in the background. These programs include basic system processes, antivirus software, system utility applications, and other software that has been previously installed. These applications and services can cause interference when you attempt to upgrade to the latest version of Windows 10.

To help you determine whether a background program is interfering with the upgrade, a «clean boot» may be needed. See How to perform a clean boot in Windows.​

Windows Setup terminated unexpectedly due to another process running in the background.

Uninstall any antivirus or antispyware software and update again.

Activate Windows 10

Activation helps verify that your copy of Windows is genuine and hasn’t been used on more devices than the Microsoft Software License Terms allow.

Checking your activation status

You’ll first want to find out if your Windows 10 is activated and linked to your Microsoft account.

It is essential that you link your Microsoft account to the Windows 10 license on your device. Linking your Microsoft account with your digital license enables you to reactivate Windows using the Activation troubleshooter whenever you make a significant hardware change.

To check activation status in Windows 10, select the Start button, and then select Settings > Update & Security and then select Activation . Your activation status will be listed next to Activation.

You’ll see one of these activation status messages on the Activation page:

Windows is activated

You are activated.

Microsoft account is not linked.

Windows is activated with a digital license

You are activated.

Your Microsoft account is not linked to your digital license.

Windows is activated with a digital license linked to your Microsoft account

You are activated.

Your Microsoft account is already linked to your digital license.

Windows is not activated

You are not activated.

You will see an error message explaining the failure.

You might need to purchase Windows 10 to activate.

If you need to purchase a license for your device, see «Purchase a Windows 10 license.»

If you have purchased a license for this device already and still receive an error message, continue to Methods of activation.

To link your Microsoft account, follow these instructions:

Sign in as an administrator to add your Microsoft account. To confirm you’re using an administrator account, select the Start button, then select Settings > Accounts > Your info . Under your name, you’ll see Administrator. If you’re not an administrator, see Create a local user or administrator account.

Confirm that the administrator account is also your Microsoft account by checking to see if an email address is displayed above Administrator. If an email address is displayed, this is a Microsoft account. If not, you’re logged in with a local account. If you don’t yet have a Microsoft account, see How to create a new Microsoft account.

Once you confirm that you’re an administrator and using your Microsoft account, go back to the Activation page, select Add an account, enter your Microsoft account and password, and then select Sign in.

After your Microsoft account has been added, on the Activation page you’ll see Windows is activated with a digital license linked to your Microsoft account.

Methods of activation

Depending on how you got your copy of Windows 10, you’ll need either a digital license or a 25-character product key to activate it. Without one of these, you won’t be able to activate your device.

A digital license (called a digital entitlement in Windows 10, Version 1511) is a method of activation in Windows 10 that doesn’t require you to enter a product key.

A product key is a 25-character code used to activate Windows. What you’ll see is PRODUCT KEY: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX.

After determining which activation method you use, follow the steps in the corresponding Activate using a digital license or Activate using a product key.

Your activation method depends on how you got your copy of Windows 10.

If you got Windows 10 by.

Upgrading to Windows 10 for free from an eligible device running a genuine copy of Windows 7 or Windows 8.1

If you associated or signed onto a Microsoft Account or associated your MSA with your digital license, that will be your MSA containing the digital license.

Buying a Windows 10 Pro upgrade from the Microsoft Store app and successfully activated Windows 10

When purchasing from Microsoft Store, a confirmation email was sent to confirm the purchase. That email address (MSA) will contain the digital license.

Being a Windows Insider and upgrading to the newest Windows 10 Insider Preview build on an eligible device that was running an activated earlier version of Windows and Windows 10 Preview

The email address that you used for your Windows Insider login will likely be the MSA containing your digital license.

Buying genuine Windows 10 from the Microsoft Store app

When purchasing from Microsoft Store, a confirmation email was sent to confirm the purchase. That email address (MSA) will contain the digital license.

Buying a PC that came with Windows 10

Find your product key either on the device packaging or on the Certificate of Authenticity (COA) attached to your device.

Buying a box copy of Windows 10 from an authorized retailer

Find your product key on a label inside the Windows 10 box.

Buying a digital copy of Windows 10 from an authorized retailer

Find your product key in the confirmation email you received after buying Windows 10 or in a digital locker accessible through the retailer’s website.

A digital license will be given to your device for Windows 10 based on the valid product key you entered.

Having a Volume Licensing agreement for Windows 10 or MSDN subscription

Your product key is available through the web portal for your program.

Buying a new or refurbished device running Windows 10

Your product key is preinstalled on your device, included with the device packaging, or included as a card or on the Certificate of Authenticity (COA) attached to the device.

If you bought a refurbished PC, the refurbisher, not Microsoft, must provide you a product key.

Buying from the Microsoft Store online

Find your product key in the confirmation email that contains the order history.

If you don’t have a digital license or a product key, you can purchase a Windows 10 digital license after installation finishes. Here’s how:

Select the Start button.

Select Settings > Update & Security > Activation .

Select Go to Store.

This opens the Microsoft Store app where you can purchase a Windows 10 digital license.

Activate using a digital license

Digital licenses are associated with your hardware and linked to your Microsoft account, so there’s nothing you need to find on your PC. You’re all set once your PC is connected to the internet and you log in to your Microsoft account.

If you are using a digital license linked to a Microsoft account, you can run setup and skip the product key option by selecting I don’t have a product key. When you sign in with your Microsoft account and connect to the internet, you will be activated.

If you have a digital license for your device, you can reinstall the same edition of Windows 10 on this device without entering a product key.

Make sure that Windows 10 is activated before you try to reinstall it. To find out, select the Start button, and then select Settings > Update & Security > Activation . You’ll be able to confirm that your Windows 10 has been activated and that your Microsoft account is associated with your digital license.

Here are the possible messages that display on the Activation page:

Windows is activated with a digital license

Your Microsoft account is not linked to your digital license. Follow instructions for Linking your Microsoft account.

Windows is activated with a digital license linked to your Microsoft account

Your Microsoft account is already linked to your digital license.

If Windows 10 isn’t activated on your device, see Get help with Windows 10 activation errors for more info.

If your digital license is not linked to your Microsoft account, follow the steps under Checking your Activation status, Linking your Microsoft account.

Once you have your account linked, then you can run setup to reinstall Windows 10. For more info about how to create installation media to reinstall Windows 10, go to the Microsoft software download website. When creating installation media, make sure to choose the edition of Windows 10 that matches the edition already installed on your device.

During reinstallation, if you’re asked to enter a product key, you can skip this step by selecting I don’t have a product key. Windows 10 will automatically activate online after the installation is complete. If you linked your digital license with your Microsoft account, be sure to sign in to the Microsoft account that is linked to the digital license.

When you make a significant hardware change to your device, such as replacing the motherboard, Windows 10 might no longer be activated.

Make sure you associate your Microsoft account to your digital license to prepare for hardware changes. The association enables you to reactivate Windows using the Activation troubleshooter if you make a significant hardware change later. For more info, see Reactivating Windows 10 after a hardware change.

If you don’t have a digital license, you’ll use a product key to activate.

Activate using a product key

A product key is a 25-character code, that looks like this:

PRODUCT KEY: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX

During installation, you’ll be prompted to enter a product key. Or, after installation, to enter the product key, select the Start button, and then select Settings > Update & Security > Activation > Update product key > Change product key.

To locate your product key, see the product key table in Activation methods, What activation method do I use, a digital license or a product key?

Note: Microsoft only keeps a record of product keys if you purchased from the Microsoft online store. You can find out if you purchased from Microsoft in your Microsoft account Order history. For more help, see Find your Windows product key.

If you have a product key, then you can use Change product key to activate Windows 10 in each of the following scenarios. Below is supplemental information that might help you with activation:

You’ll need to use a valid product key to activate Windows 10 on a device that has never had an activated copy of Windows 10 on it.

You’ll also need to use a valid product key if you’re installing an edition of Windows 10 that wasn’t previously activated on the device. For example, you’ll need a valid product key to install and activate Windows 10 Pro on a device that had Windows 10 Home installed.

During the installation, you’ll be asked to enter a valid product key. After the installation is complete, Windows 10 will automatically be activated online. To check activation status in Windows 10, select the Start button, and then select Settings > Update & Security > Activation .

If Windows 10 isn’t activated on your device, see Get help with Windows 10 activation errors for more info.

Note: In some cases, you might need to enter the Windows 10 product key that either came with the device packaging, was included as a card, or that appears on the Certificate of Authenticity (COA) attached to the device. If you don’t have a Windows 10 product key, you’ll have the option to buy one during installation.

When you buy a refurbished device running Windows 10, you’ll need to activate Windows using the product key on the Certificate of Authenticity (COA) that’s attached to your device.

If your original hardware manufacturer (OEM) changed the motherboard for you, your PC should reactivate automatically. If it doesn’t activate, your OEM might have provided a COA card with a 25-character key under a gray scratch cover. Follow these steps to get activated.:

Note: To remove the gray coating that conceals the product key, gently scratch it off using a coin or your fingernail.

Select the Start button, and then select Settings > Update & Security > Activation .

Select Change product key.

Type in the product key found on the COA and follow the instructions.

During reinstallation, you’ll be asked to enter a product key. When you type in your product key, you will have an activated edition of Windows 10.

If you finished setup and did not enter your product key, you can still enter your product key. Select the Start button, and then select Activation > Update product key > Change product key.

When you make a significant hardware change to your device, such as replacing the motherboard, Windows 10 might no longer be activated.

If you do not reinstall Windows, then you can select the Start button, and then select Activation > Update product key > Change product key to reactivate your device. Otherwise you can enter your product key during installation of Windows.

If your original hardware manufacturer (OEM) changed the motherboard for you, your PC should reactivate automatically. If it doesn’t activate, your OEM might have provided a COA card that has a gray coating over a 25-character key. Follow these steps to get activated.

Note: To remove the gray coating that conceals the product key, gently scratch it off using a coin or your fingernail.

Select the Start button, and then select Settings > Update & Security > Activation .

Select Change product key.

Type in the product key found on the COA and follow the instructions.