App is damaged and can't be opened error message for all my apps today!

[shankar2]

Hi, on almost all of my apps downloaded from the app store I'm receiving the following message:

“GraphicConverter 9” is damaged and can’t be opened. Delete “GraphicConverter 9” and download it again from the App Store.

This seems to be a bug how do I resolve this? I'm not downloading all the apps again from the app store!

 

[Kornelis]

There was a problem with the security certificates of Appstore programs:

https://www.macrumors.com/2015/11/12/mac-app-store-apps-damaged-expired-receipts-issue/

I had a couple of programs that did't want to run anymore. Deleting the effected App and reinstalling it from the App Store was the solution.

 

[shankar2]

Thanks for your correct guidance