Being asked to log into a different account on Mac App Store?

Just recently I'm being asked by the Mac App Store to log into a different account to update my apps. I've never had a second Apple ID and this computer has always belonged to me, meaning there's never been another account logged into this Mac. Screenshot of the message attached.

You have updates available for other accounts

To update this application, sign in to the account you used to purchase it.

I've tried signing out and logging back in, but to no avail. I had to remove Xcode and install it from scratch for it to work, but I don't want to do that with every app.

Any ideas? :(

To make the AppStore forget the old credentials with which an app was downloaded, remove the _MASReceipt directory in the app itself.

To do this:

1. Open Finder and navigate to Applications.
2. Ctrl+Click the application and choose "Show Package Contents".
3. Expand the Contents directory and click the _MASReceipt directory to select it.
4. Type Command+Delete to delete the directory permanently---you will be prompted for your credentials since this is a protected file.

Quit and restart AppStore, then find the application. The button should now say "Free" or "Install" instead of "Update". Clicking it will update your app to the latest version, doing so as the currently logged-in Apple user.

This can also be a temporary issue and it can clear up over time once the servers recover from some overload conditions.

I had the same issue and neither repairing permissions nor resetting SpotLight did anything to fix it.

If no email address is present in the error, the message means that it thinks that you purchased the app while logged into a different local account on your computer and the App Store does not have write permissions to update it.

It seems that something got messed up on my machine, because I only use a single local account, so I checked the permissions on Xcode.app and had to add my current local account with Read & Write access.

Once I had done that, I could then update XCode through the App Store.