Getting a 403 Forbidden Error with Nginx Proxy Manager – How to Fix It?

Ugh, the 403 forbidden nginx proxy manager error is the worst. I feel your pain! One thing that worked for me was checking the proxy host settings in Nginx Proxy Manager itself. Make sure the "Scheme" is set correctly (HTTP/HTTPS) and that the "Forward Hostname/IP" matches your backend server.

Also, try clearing your browser cache or using incognito mode. Sometimes it’s just a cached error messing with you.