1) On the clients that are showing as differs you will need to delete the contents of the following path: C:\Documents and settings\all users\application data\microsoft\crypto\RSA\s-*-**-**\
2) Then delete any scheduled tasks completely
3) Stop and restart the task scheduler service
4) Re-apply the policy from the console and verify that the machine got the policy.
5) Then wait about 3 min and it should remove the error.
A possible script would be:
net stop “task scheduler”
del “%allusersprofile%\Application Data\Microsoft\Crypto\rsa\S-1-5-18\*.*” /AS /Q
at /delete /yes
net start “task scheduler”