Can't access iTunes store from my Mac

Had the same problem.

Tried everything for 2 days, including repairing permissions, erasing files in the library, creating a new user account (there iTunes behaved "normal") and G_d knows what else.

Eventually what solved my problem:

Safari>preferences>privacy>"Block cookies and other website data" was on "Never". Checked "From third parties and advertisers" instead; went to iTunes store signed out of my acct, quit iTunes, restarted iTunes and when I signed in again to my iTunes store, everything went back to normal.

Hope this helps someone who still has some hair left on his/her head... 🙂

Yeah, I have tried that a few times before, and tried again. No luck. This is getting ridiculous. Haven't been able to sign into iTunes for 2 months now. No help from anywhere.

to fix this:

go to mac systems prefences

click user&groups

under apple id - use your apple id and password.

if its allready signed in - hit change - delete ➖ your apple id - hit done - sign in again.

open itunes - store - sign in

Nope. Tried that before as well. Doesn't work. I also cannot log into the Mac App Store to update apps there either.

Somehow I stumbles across this and it fixed everything. iTuneshelper was not correctly installed on my login items. Try this.

https://discussions.apple.com/thread/3191240

I had this same issue today, and it was so vexing! I tried restarting, reinstalling iTunes, updating my DNS settings, throwing away and rebuilding .plists, and nothing seemed to help. I knew it was a preference/cache-type issue because iTunes worked fine when I created a new user account. Then I figured it out after going through every preference setting in iTunes.

Go to the iTunes menu > Preferences > Advanced tab > Reset iTunes Store cache > and click the Reset cache button.

Voila!

(Hopefully it works for you, too.)