Disconnect your printer. Un-install your printer.

Now go to device manager.

USB Controllers. Starting at the the bottom at the USB Root Hubs, un-install everything in that section. The un-install the USB controllers. Restart your computer. Windows will find them all again and correct the problem the computer had with the USB ports, unless the USB port failed.

Download the latest drivers for your printer from here. Now try installing the printer, it will prompt you when to connect it.

Did you happen to re-install the system at one time? If so, did you install these drivers that Dell recommends.

Desktop System Software or Notebook System Software
Chipset or SMBus driver
Processor Driver (if applicable)
Video
Audio (sound)
Input Drivers (keyboard/mouse)
Modem
Network Card

They can be downloaded from here.