'92 325 power window failure

When I bought the car (325i 4 door), the driver's side window winder (the scissor) part was already broken (snapped in half). Somehow the previous owner had broken it (he said it broke when he tried to roll it up once). Anyway, I fixed that, but now the window does not want to work once again. The windown open about an inch or two and then refuses to open anymore. The motor is making noise, but nothing is happening. The backseat driver's side window also slides down while driving (about 4 inches or so) and the motor does not work. The front passenger window has symtoms similar to the driver's side front window. The only working window is the passenger side back window. Is this a common problem with the windows? At first I thought that maybe it was just a fluke that the driver's side window did not work, but when the two others failed it made me wonder if it was a common problem?

Thanks

I had window problems with my 92 325I and it was the plastic guide that slide in the window bracket attached to the bottom of the window and the regulator they whare and let the window fall off track pop off your door pannels and operate window you should see the problem right away.