I think your support team needs to reconsider how they approach their responses to tickets. They are asking normal people to check router ports, with no instructions on how to do so. Not to mention that doing this incorrectly can possibly open up your network to attacks. Not to mention that the reply itself is completely robotic and mechanical in its construction. Plus, it didn't work for the person that received the communication.
"Greetings,
Error 200 occurs when a player is unable to reach one of the game's megaservers. If you receive this error, you should try again in a few minutes. If you continue to receive this message after waiting, try the following troubleshooting steps:
Check our Service Alerts page for details about the status of the game.
Ensure that any anti-virus/firewall protection has exception rules for The Elder Scrolls Online.
Ensure the following ports are open on your modem / router:
TCP / UDP Ports 24100 through 24131
TCP / UDP Ports 24300 through 24331
TCP / UDP Ports 24500 through 24507
TCP Port 80
TCP Port 433
If you have completed these steps and are still experiencing the issue, please reply to this email with a screenshot of your error message. Please note that we are aware that some players may not be able to sign into ESO at this time.
We are investigating the issue and hope to resolve the it so players can return to normal play as soon as possible. The best way to keep up to date is by keeping an eye on the ESO Forums. You can find the forums here: Elder Scrolls Online forums
Kind regards,
The Elder Scrolls Online Team"