How To Resolve the PcaSvc.dll Missing Entry and PcaWallpaperAppDetect Error

Dealing with this kind of error after upgrading to Windows 11 24H2? Yeah, it’s kind of annoying — Windows seems to miss removing a scheduled task that calls a DLL that no longer exists. Because of course, Windows has to make it harder than necessary, right? Anyway, this problem usually pops up as a message about PCASVC.dll or the Program Compatibility Assistant Service (PcaSvc).It’s mostly harmless and just a leftover from the update, but yeah, that error message can be super distracting, especially if it keeps popping up randomly.

Just to be clear, this isn’t about a corrupted file or some malware. It’s mostly an outdated task that’s still trying to call something that’s been removed or renamed. Fixing it isn’t too tricky, but you need to dig into the Task Scheduler or restart the related service. Oh, and running a quick SFC scan helps just in case any core files got slightly banged up during the upgrade. So, here’s what you can try, step by step.

How to Fix Windows 11 Error Caused by PCASVC.dll Call

Method 1: Remove the PcaWallpaperAppDetect Task from Task Scheduler

This task is probably just sitting there, calling a DLL that no longer exists, which causes the error message. Disabling or deleting it should make that error go away — at least until something else weird happens. It applies if you see the error pop up continuously but can’t find what’s causing it. Once done, you’ll probably get rid of that annoying popup and won’t have to see the “call to missing DLL” message anymore.

1. Open the Start Menu, type Task Scheduler and launch it.
2. Navigate to Task Scheduler Library > Microsoft > Windows > Application Experience.
3. In the right pane, find PcaWallpaperAppDetect, right-click it, and choose End. Sometimes, it takes a second to actually end, so be patient.
4. Right-click again on PcaWallpaperAppDetect, then hit Disable or Delete. Just removing it usually stops the message from showing up again.
5. Close Task Scheduler. That’s it. The error message should be gone now.

On some setups, that task might be stubborn and won’t end on the first try, or maybe it reappears after reboot. But generally, disabling it does the trick.

Method 2: Restart the Program Compatibility Assistant Service (PcaSvc)

If the error is caused by the PcaSvc service either not running or stopping unexpectedly, restarting it can help. This service scans programs for compatibility issues to keep Windows smooth. If it’s stopped, Windows might keep trying to call that missing DLL and throw errors. So, making sure it’s running properly can clear that up.

1. Press Win + R to bring up the Run dialog.
2. Type services.msc and hit Enter. This opens the Services window.
3. Scroll down and find Program Compatibility Assistant. Double-click on it to open properties.
4. Set the Startup type to Automatic or Manual. Sometimes it’s set to disabled, which causes problems.
5. Click Apply and then OK.
6. Reboot the PC. If everything goes right, that should stop the error from popping up again.

The reason this helps is that if the service isn’t running, Windows might keep trying to call that nonexistent DLL, which then leads to errors.

Method 3: Run an SFC Scan to Fix System Files

Because the DLL in question is tied to system files that shouldn’t be missing or corrupted, running a System File Checker (SFC) scan can help restore any broken system files. Not sure why it works, but many times running sfc /scannow from an admin Command Prompt fixes weird errors like this — especially after a big upgrade.

1. Click the Start Menu, type Command Prompt, then right-click and select Run as administrator.
2. In the terminal, type sfc /scannow and press Enter.
3. Give it time — it’ll check your files and, if needed, replace corrupted or missing ones with cached copies stored at %WinDir%\System32\dllcache.
4. Once the scan completes, reboot and see if the error message is gone. Sometimes, it needs multiple boots to fully settle down, so don’t get discouraged if it’s not all fixed immediately.

If that doesn’t work and the error persists, the last thing might be to contact Microsoft Support or wait for an official update. But honestly, fixing that task removal and service restart is usually enough.

All in all, these steps address the root causes — outdated tasks calling missing DLLs or services that aren’t running. These fixes probably won’t cause any hiccups either, since they’re mostly about cleaning up leftover scheduler tasks or making sure Windows services are behaving. After doing this, the error message should be history. Fingers crossed this helps — it’s worked for a few other folks facing the same problem.

Summary

• Remove suspicious or outdated tasks from Task Scheduler.
• Ensure the Program Compatibility Assistant Service is running in Services.msc.
• Run sfc /scannow to fix corrupted system files.
• Reboot and check if the error message disappears.

Wrap-up

This kind of leftover from a Windows upgrade can be a real pain, but it’s usually a simple fix — especially if you’re okay with poking around in Task Scheduler and Services. If you keep seeing this error after trying all that, maybe wait for a Windows update to officially patch it out or contact support. For now, these steps should at least quiet the noise and let you get back to work — or whatever else Windows was getting in the way of.