After upgrade to MacOS Mojave, I cannot login or connect to App Store.

Yeah I had the same problem where I couldn't get into the app store and sign in from a fresh new computer, a macbook pro 13 in. I was fiddling with the files but ended up just reinstalling mojave and now I'm able to sign in but still unable to download apps from the store or update existing ones. When I click "view information" under my account it says that it cannot connect to the app store even though other pages load so it's really bizarre.

I had same issue of not being able to sign in to app store. After trying everything that was written in previous posts, this worked for me:

a) Open KeyChain Access

b) Click on System Roots

c) Double click on "DigiCert High Assurance EV root CA"

d) Expand "Trust"

e) Change "When using this certificate" from Use System Defaults to "Never Trust"

f) Restart the computer

g) Do steps a to e again but change "Never Trust" to Use System Defaults

After this, I was able to login to App Store and download apps etc.

That is what I've heard from other sources as well: this problem stems from an actual issue with Mojave itself or the version of the app store, so I believe the only solution is patience, however inconvenient, for an update.

Using AppCleaner and following Checkyorself289's directions worked for me. I did have to reboot after cleaning before I was finally able to sign in.

If you're having problems with the App Store you might try this:

1 - sign out of the App Store.

2 - enable the Debug menu in App Store:

• open the Terminal application.

• copy the command below and paste into the Terminal window:

defaults write com.apple.appstore ShowDebugMenu -bool true

followed by Enter or the Return key.

3 - launch App store and select the Debug ➙ Reset Application option:

4 - sign in and try again.

Yes, a number of people in the thread have reported this to Apple. I've been back and forth with Support and their Engineering team and have found a partial solution to a problem that I was having (High Sierra App Store co-existing with the Mojave App Store, in a folder called "Previous Content"):

• The folder couldn't be deleted, so I rebooted into Restore mode (command-R while starting up).
• From the Utilities menu, I opened Terminal and disabled System Integrity Protection by typing the following in the window:
• csrutil disable
• Then pressing enter.
• Rebooting allowed me to delete the previous version of the App Store along with Safari, etc.
• Rebooting again, after deleting and emptying the Trash, restored some of the panes in the App Store:

Sadly, though, I still can't connect to the App Store.

So, perhaps partway to a solution but not there yet. I'll update as soon as a solution is found, if I find one.

SIP can be restored using the same process but with the command csrutil enable, FYI.

I have a similar problem since a few days. I cannot connect to the App Store.

Also in system preferences (Mojave) the text says: Unable to check for updates.

In the App Store:

The store menu item is no longer working (no drop down menu) and on the left there is not even text!

(see below).

I exhausted all possibilities I found here or on the internet. (Refreshing certificates, deleting various stuff, even restoring from time machine: versions that worked previously do apparently no longer work.) Even with a new account or with safe boot the same problem.

In console there is now a number of errors (see list of events when starting app store, filtered for "app store" in the error log)

Please let me know, if someone has a novel idea:

Thank you very much for explaining in details the steps for the solution. It worked for me and it was not necessary to reinstall Mojave. Only restart was necessary after the steps described above. What is happening with Apple?

Funny enough: after trying to repair it all ways that are described on that thread without any solution, I waited. At some point the problems basically went away by themselves. Not sure, whether s.th. was changed on apple side or (I suppose this was it) a change to the company network was made; perhaps their authentification requires special ports. I simply do not know, but it is weird and extremely annoying that there are no meaningful error messages, or logs.

I also tried everything else (deleting caches folders, trustfile, updates, different internet connection, logging with different account, logging in on guest account) but this one really worked! I first was afraid I would delete something essential and then would have to reinstall everything.

Thanks!

Thank you Checkyorself289. This is the only fix that worked for me. Before the fix, the App Store would show that I am signed in but I could not see my purchased apps and and account information. It had the error "Cannot connect to App Store". I followed your instructions and after reboot, I tried to log in to the App Store but still could not connect. So I signed out and signed back in to the iCloud and reopened the App Store and bam! I can already see my purchased apps and account info!

You're true MrJingles. I thought everything was working since I saw that I was connected to the Store. But trying to download any update or any new app is still not working :-(

The issue is old and I 've never seen Apple taking so long to fix a so huge bug...

I've tried everything presented as a solution on the web : deleting plist with the Terminal, reinstalling Mojave, changing certificates settings, changing DNS servers, etc, etc.... No result.

Still not working. Geez, the apple online chat spend all my afternoon to do those tests, and told me that this is not a issue submitting to dev because "others are not having such issue". See how many folks are here?

After trying everything, this solution worked for me!

Only difference: I did not have to reinstall Mojave - just rebooted my iMac and then started AppStore and went directly to Login.

AppCleaner is really a very good tool, used it for years.

I have the same error and these steps don't solve the problem, even the advanced steps (those two files aren't in the /var/db/crls folder, for example). I posted another screenshot here: Mojave installation fails: duplicate App Stores, can't sign in with Apple ID (Macbook Pro, Late 2016)

The error screen looks like this: