The last days i tried to use Facebook registration and User upgrades. Using all of these didn't work, because the forum software seems to be unable to connect to external services. The transaction log for the user upgrades just says "Connection to PayPal failed", with a similiar response from the integrated Facebook test: "Your server could not connect to Facebook (https://graph.facebook.com). Try again later. If the issue persists, contact your host." And i did contact my host, after already searching for answers here. I asked him about firewall settings and the server not being able to connect via SSL, according to this thread: https://xenforo.com/community/threads/yet-another-facebook-integration-problem.69530/). His response: The overall settings seem to be connect for the user upgrades (IPN activated at PayPal, etc.) and Facebook (App setup with correct domains and site url), so as a beginner in server matters i'm currently not sure what i can do next. Except asking here, of course... Thanks in advance for any help! I'll try to answer any necessary questions.