http://www.macnn.com/articles/08/08/01/itunes.error.5002/
Users locked out from iTunes store
updated 01:00 pm EDT, Fri August 1, 2008
iTunes users locked out
A select handful of iTunes users have begun to experience issues logging into, and downloading items from the iTunes store. Error 5002, and error -4 have been associated with the issue, and may be a sign that users have been locked out of their iTunes accounts. Users on the Apple discussion boards seem to believe the problem may be related to changing the country of the iTunes store the user is browsing. However, it seems as though this is not the only way the error comes about. Some users have found that resetting their iTunes account password, and/or changing the settings of iTunes Shopping Cart and One-click shopping has solved the problem but this has not worked for all.
Fresh-Faced Recruit
Joined: Dec 2005
The Useful Question...
...would be to ask if this occurs before or after moving to the recent iTunes update.
Just wondering.