Find out why your computer is restarting and fix the cause

A computer that restarts without warning usually has one of four causes: a Windows update that finished installing, a driver that crashed, overheating, or a hardware failure. The fastest way to stop it is to check Windows Update first, then look at your system logs to see what triggered the last restart. If neither of those shows anything, test your cooling system and hard drive health. Most restarts can be traced and stopped within an hour.

The restart loop itself is the symptom, not the problem. Your job is to find what Windows or your hardware is trying to tell you, then address that thing directly. Turning off automatic restart will hide the problem but not fix it — your computer will still be unstable, and you may lose data.

Key Takeaways

  • Check Windows Update first: open Settings, go to Update & Security, and look at the update history to see if a restart happened right after an update installed.
  • Open Event Viewer (search for it in the Start menu) and look at the System log to see what error code or driver name appears before each restart.
  • If your computer feels hot to the touch or the fan is loud, clean the vents and check that the fan spins freely — overheating is a common cause of unexpected restarts.
  • Run Windows built-in disk check by opening Command Prompt as administrator, typing chkdsk /f, and restarting when prompted — this catches hard drive problems that trigger restarts.
  • If you find a specific driver or program causing the restart, uninstall or update it rather than disabling automatic restart, which only masks the underlying issue.

Check Windows Update and restart history

Windows often restarts automatically after installing updates, and the restart can happen even if you are in the middle of work. Open Settings by pressing Windows key + I, then click Update & Security on the left. Click View update history to see a list of recent updates with dates and times. If an update installed around the time your restarts began, that is your answer.

If you see updates installing regularly, you can delay them but not stop them permanently. Click Pause updates for 7 days to buy time, or go to Advanced options and set Active hours to the times you use your computer — Windows will not restart during those hours. Note that pausing only works for seven days at a time; after that, updates resume.

Look at the System log to find error codes

The System log records every restart and the reason for it. Search for Event Viewer in the Start menu and open it. On the left, click Windows Logs, then click System. You will see a long list of events. Look for entries labeled Critical or Error that appear right before a restart — the timestamp will help you match them to when your computer actually restarted.

Click on one of these entries and read the details. Look for a driver name (often ends in .sys), a stop code (like 0x0000007E), or a program name. Write down the exact text. If you see a driver name like nvlddmkm.sys (NVIDIA graphics) or iaStorA.sys (Intel storage), that driver is crashing and needs to be updated or rolled back. If you see a stop code, search that code online along with your computer model to find what hardware or driver is failing.

Test your cooling system and check temperatures

Overheating causes restarts because the CPU shuts itself down to avoid damage. Feel the air coming out of your computer's vents — if it is very hot, or if the fan is running constantly at high speed, your cooling system is struggling. Shut down the computer and unplug it, then use a dry cloth or soft brush to clean dust from the vents and fan blades. Dust buildup is the most common cause of overheating.

After cleaning, plug the computer back in and turn it on. If you want to monitor temperatures while the computer runs, read a free tool like HWiNFO or Core Temp. Run the tool and watch the CPU temperature. If it climbs above 90°C (194°F) under normal use, your cooling system needs service — either the thermal paste between the CPU and heatsink has dried out, or the fan is failing. At that point, contact a repair shop or the manufacturer.

Run a disk check to find hard drive problems

A failing hard drive can trigger random restarts. Windows includes a built-in tool to scan and repair disk errors. Right-click the Start menu and select Windows Terminal (Admin) or Command Prompt (Admin). Type chkdsk /f and press Enter. Windows will ask if you want to schedule the check for the next restart — type Y and press Enter.

Restart your computer. The disk check will run before Windows loads, and it may take 10 to 30 minutes depending on your drive size. Let it finish without interrupting. If the check finds errors and repairs them, your restart problem may be solved. If it finds bad sectors that cannot be repaired, your hard drive is failing and needs to be replaced.

Update or roll back drivers that are causing crashes

If the Event Viewer log shows a specific driver name before each restart, that driver is the problem. The fix depends on whether the driver is too old or too new. Open Device Manager by right-clicking the Start menu and selecting it. Find the device that matches the driver name — for example, if the log says nvlddmkm.sys, look for NVIDIA under Display adapters.

Right-click the device and select Update driver. Choose Search automatically for updated driver software. If Windows finds a newer version, install it and restart. If the problem started after a recent update, right-click the device again, select Properties, go to the Driver tab, and click Roll Back Driver to go back to the previous version. After rolling back, restart and see if the restarts stop.

Disable fast startup if other fixes do not work

Fast Startup is a Windows feature that can sometimes cause restart loops, especially if your computer has been running for a long time without a full shutdown. It is worth turning off if you have tried the steps above and still see restarts. Open Control Panel and search for Power Options. Click Choose what the power button does on the left. Click Change settings that are currently unavailable. Uncheck the box next to Turn on fast startup and click Save changes.

Restart your computer and monitor it for a few days. If the restarts stop, fast startup was the culprit. If they continue, turn fast startup back on and focus on the other causes — driver updates, cooling, or disk health.

Frequently Asked Questions

Is it safe to turn off automatic restart?

Turning off automatic restart will stop the visible restarts, but it will not fix the underlying problem. Your computer will still be crashing, and you may lose unsaved work or corrupt files. It is better to find and fix the cause. If you must disable it temporarily while troubleshooting, open System Properties (right-click This PC, select Properties, then Advanced system settings), go to the Startup and Recovery section, and uncheck "Automatically restart".

What does a blue screen of death mean?

A blue screen (also called a stop code or BSOD) appears when Windows encounters a critical error and must restart. The screen shows a stop code like 0x0000007E. Write down this code and search it online along with your computer model — it will point you to the failing driver or hardware. The code is more useful than the restart itself for finding the problem.

Can a virus cause random restarts?

Viruses can cause restarts, but they are less common than driver crashes or overheating. If you suspect malware, run Windows Defender (built into Windows) by opening Settings, going to Privacy & Security, and clicking Virus & threat protection. Click Scan options, select Full scan, and run it. If Defender finds and removes threats, restart and monitor for a few days.

Why does my computer restart right after I turn it on?

A restart loop at startup usually means a driver is crashing during the boot process. Try starting in Safe Mode by restarting, then pressing F8 or Shift + F8 repeatedly before the Windows logo appears. In Safe Mode, open Event Viewer and check the System log for the error. If Safe Mode is stable, a third-party driver is the problem — uninstall recent driver updates or software you installed before the loop started.

How long should I wait before concluding the restart problem is fixed?

Monitor your computer for at least three to five days after making a change. Some restart causes are intermittent and may not show up when ready. Keep the computer on during normal use and watch for any unexpected restarts. If you go a full week without a restart, the problem is likely solved.