Xcode can’t update / install from Mac AppStore is stuck on waiting

After hitting the Update button, the dreaded “waiting” state shows up, only to not be accompanied by any progress, shape of form.

Launching Console yields no discernible results apart from an off-putting occasional line that reads:

The connection to ACDAccountStore was invalidated.

It is time to empty the Mac AppStore caches.

  • Close the AppStore.app
  • Preferably kill the appstoreagent process
    • In a terminal: killall appstoreagent
  • Open  ~/Library/Caches/
  • Delete the com.apple.appstore folder
  • Open /private/var/folders
  • Search all of the subfolders and delete all instances of com.apple.appstore
  • Restart your Mac