Hi @losvincent, thanks for reaching out!
Does the 502 Bad Gateway response come immediately from clicking the “Activate” link on WordPress > Plugins > Installed Plugins page or at a later time like accessing Wordfence links inside the admin area?
You may benefit from clearing any site or browser caches, but if that doesn’t make a difference, deactivate all of your other plugins and then try activating Wordfence.
If it still doesn’t work when no other plugins are running, you may need to look at your server/PHP error logs (with the assistance of your host if necessary) to determine what error is occurring in the background. If you or they are unable to troubleshoot the message, feel free to paste that here in case we’ve seen it before and can point you in the right direction.
Thanks,
Peter.
