Hey bzb,
try posting this somewhere in here: https://forums.eagle.ru/forum/474-general-bugs/
Where you posted it now is out of place, and I think it will get more attention where I indicated.
Also, a quick search for the error message indicates that it seems this has almost always to do with the network blocking access to ED Servers. Are you behind a Firewall? Or in a counry that may block certain servers? Try to provide Logs with your post. You will finde them either in:
%userprofile%\Saved Games\DCS.openbeta\Logs for open beta, or
%userprofile%\Saved Games\DCS\Logs for stable
You can copy-paste the path into a Windows Explorer address bar as provided, %userprofile% will resolve to your user's home path.
Regards