If you’ve upgraded to iTunes version 8.x recently, you may have experienced a problem when trying to view items in your shopping cart, or agreeing to upgrade apps that you already have installed:
We could not complete your iTunes Store Request.
An unknown error occurred (5002).
That’s really helpful… (Read more after the fold.)
If you get the 5002 error attempting to browse your shopping cart, the favored solution is to go to iTunes Preferences, then the Store tab, and select “Buy and download using 1-Click” instead of “Buy using a shopping cart.” (Clearing the items in your cart also seems to eliminate the error message.)
Another (Mac OS X-specific) flavor of the 5002 arises if there are permission errors in or around the iTunes Music folder. According to a thread on the Apple Support Forum, the follow steps can fix the permissions problem:
- Log in using an administrator account.
- Locate
your iTunes Music folder. If you are not sure where your iTunes Music
folder is located, launch iTunes, open Preferences from the iTunes Menu
and click Advanced. This will show you where the iTunes Music Folder is
located. - Select the iTunes Music folder.
- From the File menu, choose Get Info.
- Click the disclosure triangle to open the Ownership and Permissions section of the Info window.
- Set the permissions as follows (you may be prompted to enter an administrator account password):
- Owner: access Read & Write
- Group: access Read Only
- Others: access Read Only
- Click the “Apply to enclosed items” button.
- Close the Get Info window.
If the error is generated by app update attempts, (carefully!) take the following steps, courtesy of WikiAnswers:
1. Back up Mobile Applications from /Users/myusername/Music/iTunes by
dragging them to another disk — simply moving them elsewhere on the
same disk doesn’t work, since iTunes keeps track of their location.
Duplicating the folder would likely work too, if you haven’t got
anywhere else to copy them.
2. Once you have the Mobile Applications folder backed up, and
have verified and reverified that you’ve got a copy and haven’t simply
moved the folder, open iTunes WITHOUT YOUR IPHONE/IPOD CONNECTED and
select all your applications and delete them. (if your iPhone/iPod were
connected, it would now start helpfully deleting apps)
3. When they’re all gone, quit iTunes
4. Start iTunes again and verify that you have no apps listed.
5. Drag your backup Mobile Applications folder to your open
iTunes window — if you have default iTunes settings (copy/manage my
music), then iTunes will start re-adding your applications. The nice
thing about this is that it also eliminates all the duplicate apps and
renames along the way — all those updates you keep doing don’t get rid
of older versions, so these just pile up as “Application 1″, 2, 3, etc.
You may end up saving a lot of disk space. Many apps have gone through
name changes too, so you may clear up some confusion and duplication
too.
6. Read the iTunes notices carefully — you will likely get
something like “an OLDER version of this app already exists, do you
want to replace it” (you DO), or “a NEWER version of this app already
exists, do you want to replace it” (you DON’T), or sometimes a mention
that this app already exists as the same version (replace it).
7. Quit iTunes, then restart it to “set” the changes

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Here is the real fix for this is:
1. Go to: store.apple.com/ca (or store.apple.com if you’re in the us)
2. Click account in the upper right corner and then click change account info and sign in using the same email and password that you use for itunes store
3. U R now on the account profile page. Remove ONLY the credit card numbers from the card number field-DO NOT remove the expiration date or credit card type.
4. Select where you are primarily going to be using your purchases (ie-home) from the pop up menu near the bottom of the page.
5. Click continue. If you are asked any other information, be sure to click continue after making the updates so that your changes will be saved.
6.Now go to: phobos.apple.com/accountSummary
7. Sign into the iTunes store using your account name and password
8. On the apple account information page, click the edit payment information button
9. Choose “none” for payment method and click done to save your changes.
When you are done-try to make your purchase again.
THANK YOU, THANK YOU, THANK YOU! This has been driving me absolutely nuts for months, your fix finally did the trick
D, Thank you very much from me too. You got my Itunes working again also, with your post. You have been very helpful. Fortunately my itunes just started acting up today and, thanks to you, I’ve already fixed the problem.
Thanks Z – you’re a lifesaver!
Er, D. Whoever.
Nothing is working for me, I’m trying to rent a movie and it keeps saying, “Cannot download (movie). iTunes error 5002. Please try again later.” Or something like that. Please help.
Hey… tks A LOT!!! This issue had become a headache for me.
Works perfect in the Mexico Store
THANK YOU!! The newer versions are laid out a little differently since your original instructions were posted but overall you do the same thing and I AM SO GRATEFUL FOR YOUR HELP! I’ve been going in cyber circles trying to figure out what was wrong!
I’m having the same problem. Except now, it’s telling me that the credit card number is mandatory and there’s no area where it asks where I’ll be downloading purchases. HELP!!
I’m having this issue as well, but when I try to delete my credit card information, it tells me that information is mandatory and won’t let me save my account info without it. Anyone know how to fix this error in this case?