Problems with TMDA after changing computer

I am a end-user of TMDA through Global Marine Network using XGate.
I had been using TMDA from a laptop for some time and everything was 
working fine. Then I moved from the laptop to a marine PC installed on 
my boat.
When I tried to add one address to my white list, I got a message saying "
*Error:* 	User's IP address has changed.
*Cause:* 	Your IP address has changed. This is not allowed.
*Additional:* 	Running in system-wide mode.
Attempted to read session data with euid 80, egid 80.
75.104.128.59->75.104.128.37
*Recommend:* 	Log back in </index.htm>.


I tried to uninstall TMDA from the marine PC but got the same message. 
Then I went to my laptop and was able to uninstall TMDA. I went back to 
the marine PC to reinstall TMDA from that computer, but got again the 
same message.

what should I do to get spam protection again and be able to manage my 
white and black lists from my new computer?

Bernard Lefevre