After removing and re-adding one of the Nintex apps within Office 365, the app icon no longer appears within the list ribbon.
- Re-remove the Nintex app that is no longer available in the list ribbon.
- Once the app is removed, re-add the app to the site.
- When the app is adding you will see two "ghost" versions of the app, one being added and the other being removed.
- Cancel the app that is being added to the site, and wait for the "ghost" version of the app to fully remove itself.
- Once the app is gone from Site Contents, add the app to the site one more time.
- You will only see one copy of the app within Site Contents (the version being added), and once it has finished adding, the app icon will now be available within the list ribbon.