thank you for the reply. Sadly, it didnt work. I added the IP-Range you mentioned to my Firewall rule (Exception opera.com, *.opera.com, 126.96.36.199-188.8.131.52 TCP 80/443). Now, the Error while updating is not comming immediatly, it takes about 20 seconds, then i get "Error while searching for new Updates".
I added my Computer to a "Static_Exception" on our Firewall, which passes through everything for my Computer, then i get the Updater to work, but i cannot let every Computer open through Firewall.
I also disabled my AntiVirus (TrendMicro) so there is no blocking, but it didnt changed a thing. It even worked while TrendMicro on and Firewall Static Exception.
Our Windows Firewall is, as mentioned, disabled by Group Policy.
I guess there is a URL or IP / Port which gets blocked by our Firewall, which i need to add to the Opera Updater Rule.
Thank you very much in advance!