There is error “To update this application, sign into the account you used to purchase it.” keeps showing up when I would want to upgrade my app from Apple’s app store.
At first you might thought you had entered the wrong account, just like what the error shown. But actually this was a common bug that faced by many Mac OS X users. So the resolution for this at the moment is just delete your app and reinstalling it again. To avoid deleting issue, when using some Mac app cleaning tools, you need to make sure you only remove the app within the Application folder and not all the settings files stored in other users folders.
Besides, you also need to ensure you don’t have any links to that app on your dock, because that would refrain you from getting installing properly.
I found that it doesn’t work by just removing the app from the Launchpad. That’s another weird issue.