Error 500 re-installing apps after a backup/restore

we have an issue on App installation after a backup/restore:
During a trial of the BigPicture App from the marketplace, we did a backup/restore of the whole account. Mistakenly we clicked to overwrite the user information during restore.
The restore also uninstalls the App. After we tried to reinstall it, we had the same behavior like in this post:

After approving the groups under ‘Application access configuration’ we now get this error when we try to re-install it:

Hi @Felix_sw,

Welcome to the community!

This might be caused with the differentiating clientKey, app user, etc. Might be worth contacting the app vendor and have your site’s info removed or refreshed. Issue on import/export can be found here:,