Can't File Share With Westell 6100 Modem (Resolved)

I have been using the same Westell 6100 modem for the last 3 yrs. I used it with Bellsouth, Earthlink and now (today) I'm back with Bellsouth again. The problem is that my mIRC file sharing program wont work now. No one can connect to my server. It was working perfect before I went back with Bellsouth. I also have a Belkin router but that should not have anything to do with this issue. The only 2 things that have changed is my ISP and I updated the firmware in the modem.
The computer with the mIRC program on it is not my main computer, its in my spare room and part of my home network.
I have checked every single setting in the modem, router and mIRC program and everything looks right. I have even tried the "port forwarding" settings in the Westell config page. Nothing works.
If anyone has any suggestions as to what I need to do to fix it, I would really appreciate it.
Thanks in advance!

 

List the chain of equipment from the street to your PC.

 

I have fixed the problem. I noticed the next morning that the IP passthrough that I "enabled" the day before was now "disabled ". I enabled it again, did an ipconfig release and renew and it was all better. Thanks for your reply.