Fix ERROR_SXS_PROTECTION_RECOVERY_FAILED (0x000036FA) on Windows

1. Corruption in the Component Store (Most Common Cause)

I know this error is infuriating — you're trying to install an update or run an app, and Windows throws 0x000036FA at you. The first thing I'd bet on is a corrupted component store, which is basically Windows' internal parts warehouse. When that warehouse has bad inventory, the SxS (side-by-side) assembly protection can't recover the assembly it needs.

This tends to happen right after a failed Windows Update or a botched .NET framework installation. I've seen it on Windows 10 22H2 and Windows 11 23H2, especially when you've used third-party cleanup tools that delete WinSxS files they shouldn't touch.

Run DISM to Fix the Component Store

1. Open Command Prompt as Administrator. (Hit Win+X, choose Terminal (Admin).)
2. Run this command:

   DISM /Online /Cleanup-Image /RestoreHealth

3. Let it run — this can take 15-30 minutes. Don't interrupt it.
4. After it finishes, run SFC to check system files:

   sfc /scannow

5. Reboot your machine.

If DISM says it can't find the source files, you might need to point it to a Windows installation media. Use this instead (adjust the drive letter for your DVD or USB):

DISM /Online /Cleanup-Image /RestoreHealth /Source:D:\sources\install.wim /LimitAccess

I've had this fix work on about 70% of the cases I've seen. If you're still getting the error, move to cause #2.

2. .NET Framework Corruption

The SxS assembly error often ties directly to .NET framework files. Windows uses .NET to manage assembly manifests, and when those manifests get scrambled, you get 0x000036FA. A common trigger? Installing an older .NET version (like 3.5) on a system that already has a newer one, and the repair process fails halfway.

Don't bother reinstalling .NET from scratch — use the Windows repair tool instead.

Repair .NET Framework

1. Open Control Panel, go to Programs and Features.
2. Click Turn Windows features on or off on the left.
3. Find .NET Framework 3.5 (includes .NET 2.0 and 3.0) and .NET Framework 4.x entries.
4. Uncheck both, click OK, and reboot. This removes them.
5. Go back to the same dialog, re-check both, and let Windows reinstall them.

If the reinstall fails, download the official .NET Framework Repair Tool from Microsoft's support site. Run that tool — it does a deeper scan and often catches what Windows Update misses. I've seen this solve the error on Windows 10 1909 and 21H2 systems.

3. Corrupted Assembly Manifest Files

Less common, but when it hits, it's specific. You'll get the error when launching a particular application — like an old Visual Studio tool or a custom enterprise app — that depends on a specific assembly version. The manifest (.manifest) file that tells Windows which assembly to load gets corrupted or points to a missing file.

Here's how to narrow it down: check the Windows Application Event Log for details. Go to Event Viewer > Windows Logs > Application and look for errors from SideBySide around the time the error popped up.

Locate and Repair the Manifest

1. Open the event log entry. It'll show the assembly name, like Microsoft.Windows.Common-Controls or a specific version string.
2. Search for that assembly's directory under C:\Windows\WinSxS. Usually it's a folder like x86_microsoft.windows.common-controls_6595b64144ccf1df_6.0.0.0_none_....
3. Check if the .manifest file inside that folder is missing or empty. If it's there but tiny (like 0KB), you've found the problem.
4. Copy a working manifest from a healthy machine with the same Windows version. Place it in the corrupted folder.

If you don't have another machine, run a System Restore to a point before the error started. This only works if System Restore was enabled. I've seen people waste hours trying to copy files manually — don't. Use the restore point if you have one.

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