Default [Q] Rooted/Flashed new ROM, phone is good, but now cant connect to PC via USB

I am new to Android. Just rooted, got s-off, setup TWRP, and installed Viper Rom. Everything seems to be all good on the phone.

When I attach my phone to my PC, I see the phone in my computer, but it is not letting me browse the files/folders any longer. If I try to open the phone memore or SD card, it locks up my windows explorer adn shows not responding. If I remove the micro USB cable, every think snaps back into action. I have rebooted the phone and PC I am sure its probably something stupid I am missing.

What is the deal?