can't sign into App Store

had same problems with tv app and store also last year in first beta in mojave had the same problem hopfully thses problems will be iorned out withinthe next month or so

same for me

Same here, Shows a couple of updates available, asks for password just disapears , no error.

Had the same issue yesterday, but it seems to have been a server-side issue because I was able to login on the first try today.

I can log in, but not all purchased apps validate. "This app is damaged..."

Disabling Content Caching on my network and trying again does not help.

This is only on one installation, the other works. Go figure.

Had this issue on my MacBook Air.

Was able to sign in into Mac AppStore right after I signed into Music app. My guess is that action somehow cleared stalled authentication state of AppStore.

Give it a try.

For me, I went to my settings app, signed out of my iCloud account, waited a minute and then signed back in. Then, I restarted the Mac app store app and was able to sign in and get my app updates. YMMV

I have the same obstacle with App Store 😟

Possible solution here (worked for me):

https://forums.developer.apple.com/thread/117451

Same here. I logged in and out of my Music account but still can’t log out of my Apple Account. Attempting to log out of my Apple Account does log me out of the Media and Purchases account. The error message is 'There was an error in Apple Acount preferences.'

Entering an incorrect password results in an error in the App Store. Entering the correct password appears to work, but won’t let me download.

I have same issue as well even signing out entirely of all services as i have updates to apps that arent working like OneDrive.

Thanks for the workaround.
It worked for me.

What I did:

.sign out from Music app

.laucnh App store app

.try to update an app

.sign in in App store app

my app has been updated

back to Music app, sign in and access to Apple Music as before the upgrade to Catalina.

Well it's a beta...

I had to force the music app to prompt for a password by re-authorizing it but that did the trick. I then as able to log into the app store and update the apps.

How I solved my problem: Went to Music app, scrolled to the bottom and under Managment clicked on Account. Logged in from there, after that logged in TV app and after all that managed to sign into App Store. Hope this saves someone time!