Why does Windows restart without warning?

If your Windows computer is restarting by itself, without any warning, review the troubleshooting options below for help on resolving the problem.

This page is for computers that are restarting by themselves, not computers that turn off and remain off. For computers that remain off, see: Why does my computer turn off without warning?

Software issue or error

Since the release of Windows XP, Microsoft designed Windows to automatically reboot when errors occur, such as a BSoD. Although this feature is nice for random errors, it does make it difficult to troubleshoot. Below are the steps on how this feature can be disabled and enabled in Windows XP, Vista, 7, 8, and 10.

1. From the desktop, right-click My Computer. In Windows 8 and 10, open File Explorer and right-click This PC in the left navigation pane.
2. Select the Properties option in the pop-up menu.
3. In the System Properties window, click the Advancedtab or the Advanced system settings link.
4. On the Advanced tab, click the Settingsbutton under Startup and Recovery.
5. In the Startup and Recovery window, uncheck the Automatically restart check box.
6. Click OK.

Now, if the computer generates an error, it should not automatically restart and should display an error message, most likely a BSoD.

Hardware issue or error

Some of the steps below require you to open your computer. While working inside the computer, be cautious of ESD.

Any failing hardware component in your computer could cause your computer to generate an error or reboot without warning. If you have recently attempted to add a new hardware device, remove that device to make sure it is not causing your issues.

Make sure you are not encountering any hardware conflicts by viewing Device Manager for errors.

Hardware drivers can also cause this issue. If you have recently installed new hardware drivers, you may want to try an earlier version of those drivers. Additional information and help with computer drivers is available on our drivers page.

If you updated drivers and removed any newly added hardware and the random reboots continue to occur, the computer memory is bad.

Finally, hardware devices that are not installed properly in the computer can also cause random reboots. Make sure all the cables and expansion cards are connected properly inside the computer. The best way to determine this is to disconnect and reconnect all cables and expansion cards.

Computer virus

Some computer viruses, such as the blaster virus, are designed to reboot your computer without warning. Usually, these viruses make the computer reboot every 5, 10, 15, or 30 minutes after the computer has boot.

If you believe your computer has a virus, make sure an antivirus program is installed and the virus scanner definitions are up-to-date.

Heat-related issue

Most computers today are designed to turn off or automatically reboot if the computer processor, video card, or other devices in the computer get too hot. If you have heard any abnormal noises coming from your computer recently, it could be a sign of a failing fan, which can cause hardware components to overheat.

First, verify the fan on the power supply is working by examining the back of the computer. Check if the fan is moving, moving fast, and moving smoothly (e.g., not wobbling or scraping against the insides of the power supply). For all other fans in the computer, you need to open the computer and verify all fans are working (e.g., processor fan, video card fan, and case fans).

A temperature gun, like the one shown in the picture, can gauge how hot the hardware components or integrated circuits are inside the computer.

If your BIOS monitors the speed, or RPM, of the fans, enter the BIOS setup and verify it does not report any errors. For help getting into BIOS setup, see: How to enter the BIOS or CMOS setup.

If this is a laptop computer, there is often a fan on one of the sides of the laptop. Make sure this fan is blowing air out of the laptop and check if you can feel hot air coming from the laptop. You may also consider getting a cooling pad if your laptop is getting hot often. For further help, see: What should be the temperature of my computer processor?

Issue with the operating system

If, after following the recommendations above, your computer continues to reboot, you’re likely experiencing an issue with the Microsoft Windows operating system. To help determine if this is the case, try the steps below.

1. Reboot the computer and enter BIOS setup when the computer begins to boot up.
2. After you have loaded the computer into the BIOS setup, let the computer idle for a few minutes.

• How to enter the BIOS or CMOS setup.

If the computer doesn’t reboot after idling in BIOS and you’ve tried the other solutions above, try activating a restore point in Windows before the problem started to occur. If activating a previous restore point does not work, or there are no restore points available to activate, you likely need to reinstall Microsoft Windows.

Вирус блокирует загрузку виндовс и не дает переустановить виндоус

Вирус перезагружает виндоус и блокирует безопасный режим
Здравствуйте! Подключался к чужому сотовому через кабель usb и попал вирус на мой компьютер.

Вирус убил мой антивирусник и теперь блокирует загрузку любых других
Здравствуйте! Помогите пожалуйста. Мне по почте пришло письмо, а в нем документ, с виду текстовый.

Часть 2: вирус убил мой антивирусник и блокирует загрузку любых других
Вы уж меня извините пожалуйста :pardon:, что я не продолжаю в той теме, а завела новую, просто я.

Вирус не дает установить антивирусы и блокирует сайты с антивирусами
Доброго времени суток! У меня Windows 7 (6.1.7600) (x86) Enterprise Lang: Russian(0419) на.

Определитесь что вам нужнее — лечение или переустановка.

Блокиратор когда появляется — перед загрузкой системы или после?

изменил в настройках BIOS -SATA в режиме AHCI на IDE и винда начала устанавливатся без ошибок!!
читал про режимы работы SATA RAID/AHCI Mode но не понял как режим повлиял на установку?
вообще вирус загружался, а винда нет! можно было ли его убить не путем переустановки виндоус?

Добавлено через 1 минуту
Блокиратор появляется перед загрузкой системы!

18.01.2012, 22:36 Вирус блокирует загрузку виндовс и не дает переустановить виндоус

больше похоже на обычный стоп семьбэ

Вирус блокирует загрузку многих приложений, стандартные антивирусы не помогли. Что делать?
Добрый день. Вчера перестали загружаться приложения . Не все, но многие. При запуске от имени.

Вирус блокирует установку антивирусных программ, не дает скачивать антивирусы с сайтов
При попытке скачивания или установки антивируса приложение зависает. Даже сбор логов получилось.

Вирус прилетел из чужой флешки создаёт svhost.exe, но защитник виндовс блокирует
Предистория Один человек всунул мне в ноут флешку (редактировать документ) без моего ведома (ну.

Как переустановить виндоус
Здравствуйте всем форумчанам. Подскажите как переустанавливать винду Сил и средств нет больше.

Вирус блокирует видео с ютуба, блокирует гугл и яндекс
Не даёт просматривать видео с ютуба, сам ютуб недогруженный, яндекс грузит нормально, кроме самого.

Вирус не дает установить антивирусные программы и не дает скачать антивирусы с сайтов
Когда я пытаюсь установить доктор веб либо любой другой антивирус на этапе установки выбивает.

Windows Defender — Virus & Threat Protection — Restart Now

When I launched my computer windows defender told me my virus and threat protection wasn’t turned on and to hit the «restart now» button to turn it back on. Well to no surprise that button does nothing.

First thing I did was go to google and saw a few others had this problem, common fix is that another program is messing with it, and changing the file in the registry value to 0 «fixes» it. Ya well I don’t have that file so I can’t change the value and now I’m here.

I don’t have any software installed, so there’s nothing to mess with it. Any help is appreciated.

Replies (6) 

You may prefer to install a third party antimalware program (which should disable Windows Defender).

There are a number of viable free and paid options available – take your pick.

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I tried the first solution but got stuck on step one because gpedt.msc/group policy doesnt exist.

Went to the second solution you linked and its what I already mentioned I can’t do.

Unfortunately the third link wasn’t what I’m looking for.

I would like to use Windows Defender as I always have and intend to always do, if anyone else has any suggestions I’m open ears.

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Your screenshot isn’t showing the typical “unexpected error” message that we would associate with Windows Defender being disabled in the Group Policy key, but you should reboot the PC and see if the status gets updated.

To remove the Group Policy setting that disables Windows Defender; type “cmd” in the search box; and then right-click on Command Prompt and select Run as administrator.

And then copy, paste, and enter this command:

REG DELETE «HKLM\SOFTWARE\Policies\Microsoft\Windows Defender» /v DisableAntiSpyware

Then click on the Restart button.

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I don’t really understand what you’re referring to about links not working. both of the first two links I referenced in my post included multiple solutions to try.

Same thing just happened to me when it was time for Defender to «autoupdate» and I’m guessing a bad update or issue with the update servers possibly caused the problem.

This is the first issue I’ve had with Defender since first booting up this W10 computer in the summer of 2016.

If you’ll follow the suggestion in the post of GreginMich that should fix it.

By the way I have received that «unexpected error» message.

As for me — I’m gonna be an unhappy consumer and wait a while longer and try a couple of more computer restarts (rebooting has not fixed it so far) and see if MS will fix what they broke.

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Fifth time was the charm. After fifth restart (actually this time I shut it down and waited a minute and then powered it back on) it’s back on with the green checkmark, Defender shows a virus definition of 1.265.543 and I tested it with Eicar — it’s working.

So whatever was wrong MS evidently fixed it.

That’s a good thing for the consumer.

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It looks like there might be some kind of bug or registry corruption underlying this issue, especially for people who’ve previously used third-party AV apps:

Le Boule’s method of repeatedly restarting the PC, if it’s reliable, would generally be the first thing to try. If that fails, then it might be necessary to force Windows Defender into an “always on” state by applying the Group Policy setting that enables Defender. This will have the unintended consequence of preventing Windows Defender from being disabled in the presence of any third-party AV app, so this should only be used if the “repeated restart” method fails.

To add the Group Policy setting that enables Windows Defender; type “cmd” in the search box; and then right-click on Command Prompt and select Run as administrator.

And then copy, paste, and enter this command:

REG ADD «HKLM\SOFTWARE\Policies\Microsoft\Windows Defender» /v DisableAntiSpyware /t REG_DWORD /d 0 /f

Then click the Restart button (it might be necessary to restart the PC first).

Note that this REG command is just the safe and easy way to perform the registry edit that was described in the answer to the thread cited above. It sets Windows Defender’s operational state to “always on” [DisableAntiSpyware = 0 (logical “no/never”)], whereas [DisableAntiSpyware = 1 (logical “yes/always”)] sets Defender’s operational state to “always off”; and where removing the DisableAntiSpyware registry entry simply returns Defender to its default operational state – where Defender will be automatically disabled by the installation of any third-party AV app, and automatically enabled when a third-party AV app is uninstalled.

A Virus Program to Restart the Computer

By: GH Admin | Last Updated: 09/01/2017

In this post, I will show you how to create a virus to restart the computer at every startup. That is, upon infection, the computer will get restarted every time the system is booted. As a result, the computer will become inoperable as it reboots again as soon as the desktop is loaded.

For this, the virus needs to be executed only once and from then on, it will carry out rest of the operation on its own. I have programmed this virus using the C language. If you are familiar with the C language then it is too easy to understand the logic behind the coding. The code is not posted here in this article, but you can download it from the link below.

Compiling the source code into an executable module:

UnRar the file and you should see the source code: Sysres.C

For a step-by-step compilation guide, refer my post: How to compile C Programs?

Testing and removing the virus from your PC:

You can compile and test this virus on your own PC without any fear. To test, just double-click the sysres.exe file and restart the system manually. From now on, every time the PC is booted and the desktop is loaded, your PC will restart automatically again and again.

It will not do any harm apart from automatically restarting your system. After testing it, you can remove the virus by following the below mentioned steps:

Reboot your computer in the safe mode.

(%systemroot% can be C,D,E or F)

You will find a file by name sysres.exe, delete it.

Type regedit in run. You will go to the registry editor. Here navigate to:

There, on the right site you will see an entry by name “sres“. Delete this entry. That’s it. You have now removed this virus successfully.

Logic Behind the working of this virus program:

If I do not explain the logic(Algorithm) behind the working of the virus program, I think this post would become an incomplete one. So I’ll explain the logic in a simplified manner without getting much into the technical aspects of the program. If you have further doubts, you can pass your comments.

LOGIC:

First the virus will find the Root partition (Partition on which Windows is installed).

Next, it will determine whether or not the virus file (sysres.exe) is already copied into %systemroot% -> Windows -> System.

If not it will just place a copy of itself into %systemroot% -> Windows -> System and makes a registry entry to put this virus file into the Windows startup.

Or else if the virus is already found in the %systemroot% -> Windows -> System directory (folder), then it just gives a command to restart the computer.

This process is repeated every time the PC is restarted.

How to change the icon of the executable module (This step is optional):

After you compile, the sysres.exe file that you get will have a default icon. If you send this file to your friends they may not execute it since it has a default ICON. So it is possible to change the ICON of this Sysres.exe file into any other ICON that is more trusted and looks attractive.

For example, you can change the icon into Norton antivirus ICON itself so that the people seeing this file believes that it is Norton antivirus. Or you can change its ICON into the ICON of any popular or trusted programs so that people will definitely click on it.

The detailed tutorial on changing the ICON is given in my post How to Change the ICON of an EXE File?