@agemlex, from the traces on our end it appears that the gateway couldn't be accessed. Do other connections work through the gateway (for example, local files)?
I have accepted trafic on firewall. New one error appearance: Invalid credential. In Internet Explorer my ODATA URL works correctly (on same with gateway server). Screenshort in attachment.
Hi @agemlex: this error doesn't occur on our side, so it must be coming from the gateway. Could you get the logs from the gateway and send it to us (through private message or email)? We would be interested in the logs whose name starts with GatewayInfo.
You can find out how to get logs from the gateway by following these instructions.