"Accessing iTunes store" pop up

I had the same problem. It seems that if you go through the "Authorize this Computer" process again it fixes the issue.

Thanks, that worked for me too despite having just stumbled on your reply on the 10th March 2011...

Yes, after about a week completely not using iTunes due to this annoying issue, I have found the solution through people on here. However, it was not clearly stated, so I will do such in hopes of everyone solving this issue. In my case, I had all 5 authorized computers taken up, and never authorized my computer because that would require me to have deauthorized my other computers which I was just too lazy, and did not have much motive to do. But I got on my PC and deauthorized all computers in the "account settings" under "store" in iTunes. (don't try doing this on the Accessing iTunes store affected computer, because it will bug out and not let you deauthorize.) I noticed the problem still persisted, so I authorized my macbook that was affected by this pop-up, (the bug allowed this to process) and the problem immediately subsided! Thanks a lot!

Thanks man this completely solved the problem and now I can get music again 😀

Thanks for the help. I can finally listen to my music again. It's amazing to me that tech support seems to have no idea that this problem even exists, but I'm finding it all over the place after a simple search. I've had a bunch of problems with iphoto lately too, and in general I'm just surprised by Apple's inability to troubleshoot problems. I still have 60 days left for my complimentary phone support, but I'm relying more and more on fixing problems myself...oh well.