Just to be sure, follow this:
Windows:
-Start
-(Vista, otherwise skip) Search box at bottom
-(Vista type it in, otherwise click it) Run
-Type CMD and hit enter.
-In the black box, type in: ipconfig
-Press enter.
-Under whatever connection you're using look for IP address (Possibly
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Note: Do not use one of those "what is my IP?" sites for this. That will give you your modem's IP. You don't want that.
-Make sure that IP says 192.168.0.30
-If not, change your port forwarding IP to what is displayed.
-Change the end port to 32 to be able to host for 32 players, or higher if you plan on hosting dedicated for more than 32.