October 27th-2008 Update: Celebrating the 3rd aniversary of this post with an advice from one of my readers, John: try to retype all of your iTunes account information, that worked for him.
September 11th-2008 Update: It seems that the iTunes 8 update has resulted in a number of people experiencing the 5002 error, related to updating of iPhone Apps.
Please check this thread on the Apple Forums for possible solutions: Topic : ITunes 8 Upgrade Results in 5002 unknown Error when trying to update Apps
Some of my users has been kind enough to provide possible fixes to the issue:
July 1st-2008 Update: A regular trick when you have strange errors on Mac OS X, is to perform a “Repair Disk Permissions” using the “Disk Utility” application. You should also try this if you encounter iTunes error 5002. Thanks to David from Macnyt.dk for making that suggestion.
May 15th-2008 Update: The most recent comments points to a problem with missing credit card security codes, so please review your iTunes account information.
April 2nd-2008 Update: It seems that a recent update to iTunes has made this error much more common, look to the bottom of the comment-stream to get the latest.
There’s no clear solution to the problem, but re-registering with iTunes Music Store, and/or contact iTunes can,sometimes, fix the problem.
April 4th-2008 Update: Concensus is building around something we’ve been focusing in on for a while, that is DON’T EVER USE saved shopping carts. Due to an error in iTunes, you’ll get the 5002 error, if a product you’ve added to the shopping cart, is removed from iTunes Music Store, before you go to check-up.
iTunes Music Store seems to revise their catalogue a lot, especially tail-coating a new product launch, this is why it seems to be related to new versions of iTunes.
This blog-post is, by far, the biggest driver of traffic to my website, and if you read the comment-stream, you’ll notice a lot of frustrations, Apple, PLEASE recognise this problem, and FIX it – I’ll teel it in words you MIGHT understand: YOU’RE LOOSING BUSINESS!
Kim Bach, April 2nd and 4th 2008
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I recently made my first purchase on iTunes, but I kept getting an error 5002 when trying to authorise my PowerBook. After trying again and again I gave up on it, and sent an e-mail to Apple Support, and they promissed an answer in 72 hours. Two weeks later, still no answer, so I turned to the support pages in iTunes Music Store, and there’s no useful information on error 5002.