Fix ERROR_SXS_XML_E_BADXMLDECL (0x000036E8)

Bad XML declaration in a manifest file. This usually happens after a failed update or a rogue app install. The fix is simple: find and fix the broken manifest.

Quick answer: Run sfc /scannow and DISM /Online /Cleanup-Image /RestoreHealth from an elevated command prompt. If that doesn't work, find the broken manifest with Event Viewer, then fix or replace it.

This error trips up a lot of people. The first time I saw it, I was staring at a blue screen after a failed Windows 10 22H2 update. The error code 0X000036E8 means the XML parser hit a bad declaration in a .manifest file—something like with a typo or missing encoding attribute. The system file checker usually catches it, but if it doesn't, you're stuck with apps crashing or Windows refusing to boot.

I've seen this most often with older software that ships its own manifest (think SAPI text-to-speech or legacy printer drivers) and after a botched Windows update that corrupts a system manifest. The key: you need to find which manifest blew up. Event Viewer is your friend here.

Fix 1: Let Windows fix itself with SFC and DISM

Start here. It works 80% of the time.

Open Command Prompt as Administrator (Win+R, type cmd, press Ctrl+Shift+Enter).
Run sfc /scannow. Wait for it to finish—this can take 15 minutes on an HDD.
If SFC reports errors, run DISM /Online /Cleanup-Image /RestoreHealth. This fixes the component store that SFC uses.
Reboot. If the error is gone, you're done.

If SFC says it found errors but couldn't fix them, move to Fix 2.

Fix 2: Hunt down the broken manifest manually

This is the real fix when SFC fails. You need to find the exact manifest file.

Step 1: Check Event Viewer

Open Event Viewer (Win+R, eventvwr.msc). Go to Windows Logs > System. Look for events with Source SideBySide or Application Error near the time of the error. The event details usually include the manifest path, like C:\Windows\WinSxS\Manifests\amd64_microsoft-windows-something_31bf3856ad364e35_10.0.19041.1_none_123abc.manifest.

Write down that path. That's your culprit.

Step 2: Examine and fix the manifest

Open the manifest file in Notepad (make a backup first by copying it to your desktop). Look at the first line—it should look like this:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>

Common issues I've seen:

Missing encoding="UTF-8"—add it.
A stray space or line break before the <?xml tag—delete it.
Wrong version like version="1.1"—change back to 1.0.
The whole line is missing—add it from a known-good manifest.

After fixing, save the file (you might need to take ownership if it's a system manifest). Reboot.

Fix 3: Replace the manifest from a known-good copy

If the manifest is beyond repair (or you don't trust your edit), pull a clean copy from another machine with the same Windows version and build. Or use this command to extract it from your own install media:

dism /Get-WimInfo /WimFile:D:\sources\install.wim

(Note the index number of your edition, then:)
dism /Mount-Image /ImageFile:D:\sources\install.wim /Index:1 /MountDir:C:\Mount
dir /s C:\Mount\Windows\WinSxS\Manifests\*manifest-name*

Copy the file from the mount to the real path. Then dismount with dism /Unmount-Image /MountDir:C:\Mount /Discard.

This is overkill for most people. Only do it if SFC and manual editing fail.

Prevention tip: Avoid the common trigger

This error rarely happens on its own. It's almost always triggered by one of these:

Partial Windows update—don't force shutdown during updates. Let them finish, even if it takes an hour.
Third-party software that installs side-by-side manifests—think Adobe Creative Cloud, old Visual C++ runtimes, or speech engines. Uninstall the offending app if the error keeps coming back.
Editing system files directly—if you were messing with WinSxS manifests to customize something, stop. You'll break things.

If you run into this again, check Event Viewer first. It saves you hours of guessing.