Univention - new Installation and APP Center Start schlägt fehl - Zertifikatsfehler ssl.c645:

Hello Forum,

can somebody help me ?

I have installed a new UCS Server and now i become the following Error Message when i start from the univention portal the App Center.

Es gibt ein Problem mit dem Zertifikat des App Center Servers https://appcenter.software-univention.de. ((_ssl.c 645.c: The handshake operation timed out".))

Thanks for your help

Sorry, it was my Firewall (Fortigate) it works with a Proxy. I have solved the problem.