If T3C system was working fine and from some time point it is not working anymore, please verify what changes has been made in network and infrastructure configuration and Internet connection in your institution. Often it happens, that after weekend the connection with T3C Server is not working due some local infrastructure maintenance.
Open an internet browser and try to access multiple sites on the Internet. If you have any problems, please contact your ISP or network administrator.
Verify the availability of T3C Server at https://cs.t3c.sk:
If T3C Server is available, but T3C Service does not communicate, this may be a problem with proxy servers. Please verify your network settings. See also the proxy server setup procedure.
If T3C Server is available, but T3C Service does not communicate, network communications may be blocked by a Firewall. Try to temporarily disable the Firewall and verify connection - in T3C Console menu select View/Update from the T3C Server.