Since Windows Update error 0x80242fff is essentially an Update Handler error, you need to check these log files and carry out this fix to resolve the issue.
Here’s a quick guide on running the Windows Update troubleshooter to resolve the 0x80242fff error code on Windows: Start by pressing a Run dialog box by pressing Windows key + R.
If you are not able to update Windows 10 because of an error code 0X80242FFF, try applying these workarounds – Note: Before you apply any solution, make sure to create a system restore point.