itunes error 5002
I am having trouble downloading digital copies. I enter the redemption code with the disc in the drive and then after entering my password to redeem the copy from the store it either states "We Could not complete your itunes store request. The iTunes store is temporarily unavailable. Please try again later." I don't have any problems downloading something from the store itself (I tried a free app and it worked just fine).
Any suggestions out there? I've done a lot of things that some of the threads say worked for others, but they didn't work for me. I'd appreciate any help.
Thanks.
MacBook Pro, OS X Mountain Lion (10.8.2)