I have seen this happen before but with two different things causing the problem.
1) Corrupted windows user profile. Two test create another user ID login with it on windows XP and try to run the desktop manager, if it works you likely have a corrupted windows user profile. To fix rename the user profile folder in my documents and settings. Remove and re add the users account and login. This will create a new user profile; all the data from the old profile .cookies, my documents, desktop will need to be copied back to the new profile.(Do not copy the ntuser.dat as that is the file that caused the problem and was replaced by making the new profile)
2) MacAfee antivirus. Un install MacAfee and re install the desktop manager re install MacAfee antivirus.
These have worked for me.