The easiest way is to click start>run enter "cmd" without the quotes and hit enter. This will open a command prompt which you can then run "ipconfig" in without the quotes.
Your IP will be listed here.
What game are you trying to use this with? If SWTOR, can you make sure the class name and window title fields are empty in the server?
I'm not certain whether the error message you are getting is "couldn't detect swtor client" in which case you are connected to the server and may need to do the above.
Otherwise can you show me the IP and subnet on your pc (from ipconfig) as well as the IP and subnet of your phone when connected to wifi (from wireless settings and tapping on your access point name).