My unit isn't bricked. Everything works except it won't be seen by my PC to do updates.

(I have 4 units, all with this problem, one is pin locked and I don't know the pin my sister used and she doesn't remember it, and lost all paperwork in Sandy when her house was washed away, one has a white screen, and the last one works but won't charge or access usb.)

I can't get into any diagnostic screen that lets me turn on the mass storage option instead of auto detect, and using updater.exe says that there are no updates for my unit. I think the firmware is corrupt and I want to wipe the unit and reload it with the factory load. But, can't get into USB mode to even start.