Applications can invite users to a group by issuing a POST request to /GROUP_ID/members/USER_ID with an app access_token.
When I do this with a user who is a tester everything works fine. If I try this with a non tester i get the error message:
(#3) Application must be whitelisted or users must be testers.
Anyone an idea what this means? I cannot find this error message anywhere.
Regards, Roy
I think your application is proably in sandbox mode. Try to change this in app settings, i think this would help.
Best regards
Chris