How to get eTomi to Work under Windows XP Service Pack2 Release Candidate 2(xpsp2 rc2)
If you cannot connect to any of the networks or your experience seems degraded with eTomi and you don't have any other firewalls blocking access, this may be because of the Windows XP firewall. To keep the firewall on, but allow eTomi to work properly (also called port forwarding), follow these steps:
1)Go to the Start menu, click on Control Panel.
2)In Classic View, go to the Windows Firewall icon. Double click it.
3)When a dialogue box pops up, make sure the On (recommended) radio button is selected. Then make sure that the "Dont' Allow exceptions" check box is unchecked.
4)Go to the Exceptions tab, and press the Button "Add Program" and select eTomi, if it doesn't show up on the list, browse for it; you'll most likely find it under "C:\Program Files\eTomi\eTomi.exe"
5)Press OK
6)Next, we have to open port 6346 for eTomi to communicate through. Click the Add Port button and type in eTomi for the name and put in 6346 for the port. Select TCP. Note that if you choose to use a port other than 6346 in the eTomi settings (eTomi Settings-->Internet-->Connection: PORT), you should be configuring the firewall for this port.
7)Then, repeat the above steps to open up a new port, but this time select UDP.
8)Press OK.
9)In the Change Scope dialogue box, select Any Computer
10)Now, go into eTomi, go to Tools, then Press " eTomi Settings...". And select Connection on the left hand side. Then in the Port: box put 6346. Or, if you choose to use a different port, make sure the windows firewall is configured for this port. There is no performance penalty for using a port other than 6346.
11)Reconnect to the eTomi Network(s).
12)You can, in the eTomi connection settings, put a check in the box labeled "I can accept incoming connections".
Hopefully these steps solve your problems.
Also see this Microsoft TechNet article for more.