After updated to macos catalina my itunes store show error 11556 and I cannot connect my apple ID with itunes store. Please help.

Solution 2 worked for me.

Thank you

Solution 2 worked for me.

Thank you

This is as useful as saying "just buy a new computer, problem solved!"

Not only did this not work for me, but it has now made it impossible to use email, icloud, books, and anything else that requires an icloud password!

@Tom Bola, this didn't work for me either. When trying to sign in the Music app I get, unknown error. Now I can't sign in to iCloud either! Ugh!

Whoops - spoke too soon on the My Photo Stream front. It's still not working. But Music, TV and the rest are fine.

this worked fine for me, but local mails on my Mac were gone, imported them from a backup, everything works great.

Mac Os Catalina works great now on my Mac Pro Mid 2010, thanks.

I have the same problem but solution 1 and 2 did not work for me. Any other suggestions? I really would like to hear my music again ;-)

Did you restart your computer?

Yes I did. No change still no login on music

Thank you very much!!! This solution fixed the problem :D

Thank you, now all it's ok

Thank you so much!

Solution 2 worked for me too.

I needed to restart to login on icloud via settings.

Many thanks; that was beyond ingenious. Fixed it for me as well.