Originally Posted by catmek64

I've been having usb mass storage problems the last week, also. Nothing would fix it, including trying 3 other puters, one an XP. This, a Skyrocket. Then I stumbled upon this idea - from a guy in India.

Quote -
" Cannot connect to Windows7 64 bit no matter what
« Reply #32 on: December 21, 2011, 12:59:07 AM »

Hey guys, I suffered with the same issue right after buying my GT-I9100G 2 days ago. Windows 7 didn't recognize the phone and device manager kept showing 7 unknown devices and a 'comneon suspend' device. No drivers or anything worked.
Here is the 'proper' fix to this:

The problem is not with Kies or Windows 7 or the drivers. It is the phone.

1. Either install latest Kies OR just install compatible USB drivers
2. Before connecting the phone, open the keypad and dial *#7284#
you will see a menu for UART and USB.
3. Under USB, select PDA. If PDA is already selected, select MODEM and then back to PDA
4. Don't worry about USB debugging or anything, just connect your phone to the PC
Everything will work as it is intended to whether you use Kies, no Kies or just Mass storage "

A footnote = that's (star, pound 7284 pound) no spaces. Worked immediately with mine. I hope that resolves some of your SII or Skyrocket problems. Unfortunately, it didn't work on my Captivate.