It is possible that Microsoft forgot to remove the task from the Task Scheduler, which is why it continues to call the entry point, resulting in this issue. Even though it causes no issues other than displaying the error message, several users have been concerned about this error. PCASVC.dll, also known as the Program Compatibility Assistant Service (PcaSvc), is responsible for detecting and fixing compatibility issues with old programs running on the latest Windows version. Since the PCASVC.dll is a critical file tied to the Program Compatibility Assistant Service, it should not be corrupted. Otherwise, it could lead to this error. Apart from the mentioned causes, the error may also appear if the PcaSvc service stops running in the background. Now that we have understood the causes, we can move on to the solutions to this issue.
1. Delete the PcaWallpaperAppDetect from the Task Scheduler
As mentioned earlier, the PcaWallpaperAppDetect task in the Windows Task Scheduler keeps calling an entry point that no longer exists, resulting in this error. To fix this, we can disable the PcaWallpaperAppDetect task from the Windows Task Scheduler.
2. Restart the PcaSvc Service
Another cause that could lead to this issue is the stopped PcaSvc service. This service monitors and detects compatibility issues with installed programs. Therefore, ensure this service is running.
3. Run the SFC Command
Since PCASVC.dll is tied to the Program Compatibility Assistant, which is responsible for the PCA functionality, it should not be corrupted or missing. Otherwise, it could lead to the PCASVC.dll missing entry error message. Therefore, we can try restoring the PCASVC.dll file by running the SFC command, a command-line utility that checks for the crucial system files and replaces them with the cached copy from the compressed folder located at In the end, if the issue persists, you can contact Microsoft Support for further guidance.
