O.k. lets try a few things.
1. follow this link
http://www.tsviewer.com/index.php?page=ts_viewer&ID=84367&n=Call+of+Duty+5click on the server IP then enter the password.
2. Can you get on any other TS? are you behind a modem or router or both? Have you forwarded any ports lately? Try resetting your modem/router by turning off the power and disconnecting it from your computer then reconnecting it and turning the power back on.
3. If none of this works, head over to the Teamspeak forums and see what you can find
4. You could try reinstalling TS. (don't know if this would help)
5. We had several people on TS tonight so I don't believe it's the server.
could you post the error message.
was it something like could not find teamspeak running on the server?