getting into chat

I'm having difficulty getting into the chat room. When I sent an email to help@radiantrecovery.com, I got this message back: The following message to was undeliverable.
The reason for the problem:
5.1.0 - Unknown address error 550-'No Such User Here'
When I try to get into chat, I see a large box that's empty except for a teensy tiny box in the upper left corner with a small red x in it. Then below the large box, there's a Sigma Chat logo, then:

If you love our chat room and want one, click the button above

Back to YLD Members Manual

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©Kathleen DesMaisons 2005 All rights reserved

email: radiantkd@mindspring.com

Any help you can provide will be appreciated! I don't know if my computer is Java enabled or not. I vaguely remember trying to figure that out several weeks ago and getting stymied.
Shelagh