When I try to update Plesk from 11.5 to 12, I got the following error:
Error message or request description : Parallels Panel pre-upgrade checking...
WARNING: Starting from Parallels Plesk 12.0, MyLittleAdmin 2000 is no longer supported.
Server is currently having MyLittleAdmin 2000 version, which is no longer supported by Plesk.
Proceed to upgrade Plesk with the warning message or upgrade MyLittleAdmin to 2005 or 2008 manually. After upgrading MyLittleAdmin to a higher version warning message will disappear.