Can't sign in to Mac App Store

[russell_314]

I'm signed in to iCloud, iTunes and whatever but it won't let me sign in to the Mac App Store. When I click the sign in button on the bottom left a window pops up with my Apple ID filled in and I put the password in the bottom field. When I put the correct password in, click "Sign In" the pop up goes away and nothing happens. For troubleshooting purposes I tried an incorrect password and I get "Your Apple ID or password is incorrect." If I try to purchase something (A free item) I get the message "An error occurred during purchase. The operation couldn’t be completed. (com.apple.commerce.client error 500.)" Your only option is to click "OK"

What I've done to try and fix this. Signed in an out of iTunes just to see if there is a problem with my Apple ID. I deleted the "com.apple.appstore.plist." rebooted, and I get the welcome to the App Store pop up but the same problem.

I'm on a 2018 Mac mini that's about a week old, has no software or apps installed other than what came from the factory. I take that back I did Software Update so it's currently running the current version 10.14.3. Also FYI in case I'm overlooking something obvious this is my first Mac in about ten years.

 

[russell_314]

Okay the problem is solved so posting my fix here in case someone else has the same issue.

I went to my home folder, then Library then, Preferences (You may have to unhide the Library folder in Finder View Options)

In the Preferences folder I moved three files to the trash (Don't worry your Mac will automatically recreate them)

com.apple.appstore.commerce.plist
com.apple.AppStore.plist
com.apple.appstored.plist

Then I restarted my Mac

After this I opened the App Store then on the menu bar at the top of the screen I went to Preferences (The menu bar and not the previously mentioned folder) then used the sign in button in that Preferences window. I'm not sure if signing in using the button on the bottom left of the App Store window would have done the same thing but just posting the exact steps I took to solve the problem.

This is a fix I found on several websites but the ones I found didn't mention the last file

 

[macuser_123]

Second the above. I had this exact same problem and trashing those plists allowed me to sign in.
[doublepost=1550515551][/doublepost]BTW, I got the same Mac mini 2018. It is asking to update some of the apps it came with (Keynote, iMovie, etc.), but when I go to the App store to upgrade them it won't allow it saying I'm not the person who downloaded them or something like that. Not sure what that means. I did do a migration assistant from an older machine so maybe I was logged into a different AppleID on my old machine on the App store so I'll mess around with that but wanted to see if you were successful in updating those.

thanks.

 

[russell_314]

Second the above. I had this exact same problem and trashing those plists allowed me to sign in.
[doublepost=1550515551][/doublepost]BTW, I got the same Mac mini 2018. It is asking to update some of the apps it came with (Keynote, iMovie, etc.), but when I go to the App store to upgrade them it won't allow it saying I'm not the person who downloaded them or something like that. Not sure what that means. I did do a migration assistant from an older machine so maybe I was logged into a different AppleID on my old machine on the App store so I'll mess around with that but wanted to see if you were successful in updating those.

thanks.

Mine doesn't show anything needs to be updated but I just got it so maybe the latest versions of the apps were installed. You could always take it to the Apple store and have them look at it. That's one thing I like about the mini vs iMac when it comes to portability.

 

[macuser_123]

Ok, I figured it out, if you click your username on the bottom left, it takes you to your previous purchases, and you can "claim" the preinstalled apps. Or, as I did, you can just delete them since I don't plan on using them and redownload fresh version later on since they are free anyways.

 

[russell_314]

I just saw Apple replied to my online support request about this issue. I think they just read the topic and paste a few support links. This support person emailed me a link on how to update iTunes on a iPhone, iPad, or iPod... Really Apple?