Drop down fields not working

If drop downs stop working in XP or Windows 7 do the following:

Open SME
Go to Help> Tech Support Utilities> Code 833 (opens to User profile folder)
Locate the folder named Misc
Rename the folder to Misc.old or delete it (it will be recreated on opening of SME)
Close the Windows Explorer
Log out of SME
Log back into SME and your drop downs should not fill properly