Every now and then, customers contact us about certain error messages they see when downloading our app from the Mac App Store. Such error messages include “Screens 4.app is damaged and can’t be opened. Delete Screens 4.app and download it again from the App Store” or “This application can’t be verified.”
While we’re happy to assist our users as much as possible, it’s important to understand that Mac App Store purchases and downloads are controlled exclusively by Apple. This means that we cannot directly fix or repair the damaged files which are causing these error messages.
Here are some steps we’ve found that can help work around these error messages. We recommend you carry them out in the order we’ve posted them here.
- Delete the app from your Mac via the Launchpad app. (Deleting is more effective than merely dragging it to the Trash or by other methods.) Within the Launchpad, click and hold on the app icon, then click the black “X” icon that appears.
- Log out of the Mac App Store (from the menu bar, choose Store > Sign Out).
- Restart your Mac.
- Log back in to the Mac App Store (Store > Sign In), then switch to the Purchases tab and click the Install button next to the app name to reinstall. You can also follow these instructions from Apple.
If this doesn’t help, we’ve also heard reports that this issue can be solved by temporarily creating a new administrator user account on your Mac. Log into that administrator account to install the app, then switch back to your primary account to use it. You can remove the temporary account once that’s sorted out!
If you’re still encountering difficulty downloading from the Mac App Store, Apple’s support channel will have the most insight into their systems so we recommend contacting them directly.