Windows 11 KB5077181 Causing Boot Loops? Here's How to Fix It

You install the latest Windows 11 update, restart, and your PC restarts again. And again. It never reaches the desktop.

That is what some users reported after KB5077181, the February 2026 cumulative update for Windows 11. This guide explains what was reported, how to tell if it is your problem, and how to recover step by step.

Once you're back in Windows, it also helps to know what changed on your PC after an update. This guide to startup change alerts explains one way to see new startup entries and processes.

Disclosure: I'm the developer of SysPulse, mentioned at the end. All fixes below work without it.

Note: The problem reports date from February 2026 and come from user forums and news sites, not from a verified count. Microsoft's status can change, so check the Windows Release Health page for your version before you act.

Quick Fix for the KB5077181 Boot Loop

1. If Windows still starts: Settings → Windows Update → Update history → Uninstall updates → KB5077181
2. If it keeps restarting: boot into the Windows Recovery Environment (WinRE) and choose Troubleshoot → Advanced options → Uninstall Updates → Uninstall latest quality update
3. After it works again, pause Windows Update so the update doesn't install again immediately

Details for each step are below.

What Is KB5077181?

KB5077181 is a cumulative security and quality update for Windows 11 versions 24H2 and 25H2, released on February 10, 2026. It is part of the February 2026 Patch Tuesday release.

Reported Symptoms After KB5077181

Users reported different problems after installing it:

• Boot loop: the PC restarts repeatedly, sometimes many times, without reaching the desktop
• Sign-in errors: System Event Notification Service (SENS) errors at sign-in
• Network problems: Wi-Fi connected but no internet, or DHCP failures
• Install errors: error codes 0x800f0983 and 0x800f0991 while installing the update

Not every device was affected. Reports suggest it depends on the hardware or configuration, and the root cause was not clearly identified in the sources I read.

What Did Microsoft Say?

When these reports first appeared in mid-February 2026, news sites noted that Microsoft's release page did not list the issue as a known problem. Things may have changed since then, so check the Windows Release Health page for your version of Windows 11.

For accuracy: Microsoft's resolved-issues page for Windows 11 25H2 does mention KB5077181 in a different issue, where some Samsung devices lost access to the C: drive. Microsoft and Samsung linked that to the Samsung Galaxy Connect app, not to the Windows update itself. I could not find a boot-loop entry on that page.

Fix 1: If Windows Still Starts, Uninstall the Update

1. Open Settings → Windows Update → Update history
2. Scroll down and choose Uninstall updates
3. Find KB5077181, select it, and choose Uninstall
4. Restart your PC

Or from an administrator Command Prompt:

wusa /uninstall /kb:5077181 /quiet /norestart

Then restart.

Fix 2: If the PC Keeps Restarting (Boot Loop)

You need the Windows Recovery Environment (WinRE).

How to open WinRE:

• Turn the PC on, and force it off while Windows is loading. Repeat this up to three times. Windows should then start in recovery mode.
• Or boot from a Windows installation USB and choose Repair your computer.

Then:

1. Choose Troubleshoot → Advanced options → Uninstall Updates
2. Choose Uninstall latest quality update
3. Confirm and let it finish
4. Restart

If your drive is encrypted with BitLocker, Windows may ask for your recovery key. Find it in your Microsoft account (account.microsoft.com/devices/recoverykey) before you start.

Advanced: Remove the Update with DISM (Only If the Option Above Fails)

In WinRE, open Troubleshoot → Advanced options → Command Prompt. The Windows drive letter in WinRE may not be C:, so check first with dir. Then:

dism /Image:C:\ /Get-Packages
dism /Image:C:\ /Remove-Package /PackageName:<the package name from the list>

Only remove a package you have identified as belonging to KB5077181. If you are not sure, use the Uninstall Updates option above.

Fix 3: Network Not Working After the Update

If Windows starts but the internet doesn't work, try these in an administrator Command Prompt:

ipconfig /release
ipconfig /renew
netsh winsock reset

Restart the PC afterwards. If it still fails, uninstall the update (Fix 1).

Fix 4: The Update Fails to Install (0x800f0983 or 0x800f0991)

1. Run the Windows Update troubleshooter (Settings → System → Troubleshoot → Other troubleshooters)
2. Repair system files:

   DISM /Online /Cleanup-Image /RestoreHealth
   sfc /scannow

1. Restart and try again, or wait for the next cumulative update

Pause Updates So It Doesn't Reinstall

After uninstalling, Windows may try to install the update again.

1. Open Settings → Windows Update
2. Choose Pause updates and pick a period

Pausing is temporary. Uninstalling also removes that update's security fixes, so install a later update when it is available, and back up your files first.

How to Reduce the Risk Next Time

• Back up important files before large updates
• Create a restore point before updating
• Pause updates for a week or two after release if you can't afford downtime
• Make sure you know your BitLocker recovery key and have a Windows USB available
• In a business, test updates on a few PCs before deploying them widely

After Recovery: Check What Changed

After a big update, new startup entries or background processes can appear, and updates are a common time for software to change settings. A quick check helps you spot anything unexpected:

• Task Manager → Startup apps
• Task Manager → Processes for unfamiliar names

For the steps, see How to Find Hidden Programs Running on Windows Before They Become a Security Problem.

A boot loop is not malware by itself. It is much more likely an update or driver problem. If the PC restarts on its own without an update, read Why Does Windows Suddenly Restart by Itself?

Staying Aware of Changes With SysPulse

I built SysPulse, a lightweight Windows monitor, to show what changes on a PC when you're not looking. It sends a Telegram alert when it notices:

• A new process — name and full file path
• A new startup entry
• A USB drive being connected
• CPU, RAM, or disk usage crossing a threshold you set

It can't fix update problems and it doesn't detect a boot loop. Checks run on a schedule, so alerts arrive shortly after a change. USB connections are checked every 60 seconds and startup entries every 5 minutes. It is not antivirus and doesn't replace it. It runs locally, typically uses under 30 MB of RAM, and doesn't read your personal files.

SysPulse is a paid tool with a one-time license and a 7-day refund.

More: startup change alerts · process alerts · syspulse.pro

Frequently Asked Questions

How do I fix the Windows 11 boot loop after KB5077181?
If Windows can't start, open the Windows Recovery Environment and choose Troubleshoot → Advanced options → Uninstall Updates → Uninstall latest quality update. Then pause Windows Update.

How do I uninstall KB5077181?
In Settings → Windows Update → Update history → Uninstall updates, select KB5077181 and uninstall it. You can also run wusa /uninstall /kb:5077181 /quiet /norestart in an administrator Command Prompt.

Does KB5077181 affect everyone?
No. Reports describe a subset of devices, and the pattern looked configuration-specific. Most users installed it without problems.

Is it safe to uninstall KB5077181?
Uninstalling is a normal troubleshooting step, but it also removes that update's security fixes. Install a later cumulative update when it is available.

Why is my Windows 11 PC stuck restarting after an update?
Updates can conflict with drivers, firmware or system configuration on some devices. Uninstalling the latest quality update from the recovery environment usually gets the PC booting again.

Do I need my BitLocker key to use recovery mode?
Possibly. If the drive is encrypted, Windows may ask for the recovery key. Find it in your Microsoft account before you start.

Can a boot loop mean my PC was hacked?
Rarely. A boot loop right after an update points to the update itself. If you see other signs, such as unknown processes or disabled security, see How to Tell If Your Windows PC Has Been Hacked (11 Warning Signs).

Sources

• Windows 11 KB5077181 Security Update Causing Some Devices to Restart in an Infinite Loop (Cyber Security News)
• How to Fix KB5077181 Update Triggering Restart Loops & Network Failures in Windows 11 (HTMD Blog)
• Resolved issues in Windows 11, version 25H2 (Microsoft Learn)