Error after Installation

Hello, i’ve installed Grav on my server an i got This Error:
This is my first time, i install grav.

Thanks for Help
Julian Seidl

Sorry for my bad English

Seems like your webserver is behind a firewall or proxy? if so you mind need to set the gpm.proxy_url configuration option in the user/config/system.yaml file…

Read this Configuration document for help.