I'm posting this for a friend of mine. I'm part of a Dofus (MMORPG) Guild and we are currently trying to switch from using Skype to TS3.
For that sake I rented a private server. For nearly all members it works without problem but one.

Here is what the client log show:
30.08.2011 20:17:39 Info No TSDNS found at "*******.instantts.net"
30.08.2011 20:17:48 Info No TSDNS found at "instantts.net"

and what TS3 shows in the chat box (original in german):
<20:17:27> Versuche den Hostnamen *******.instantts.net aufzulösen
<20:17:48> Hostname '*******.instantts.net' konnte nicht aufgelöst werden

and translated:
<20:17:27> attempts to resolve the host name *******.instantts.net
<20:17:48> Host Name '*******.instantts.net' could not be resolved

I already contacted the support for my server and they said the address is wrong that the person enters, but we have correctly entered it and have done it multiply time.
Any idea what the problem could be?

PS: please move the thread if its placed in the wrong section. just didn't know where to put it.