XP forgets USB's?

I have two desktop computers running XP. Both have various usb devices installed on a USB hub. The Keyboards on both are USB and they never fail to be recognized possibly because they are plugged into one the computer usb ports. The HP Printers that are attached to both sometimes are 'forgotten'...and the error sign comes up and says no printer is found. I unplug the USB hub, plug it back in and XP then 'sees' the other USB items, printer, flatbed scanner, and film scanner.
Any clue as to why this happens? Thanks.

 

What chipset does your mainboard have? If it has a Via chipset, you need to go to Via and install the Hyperion drivers for your board. Also visit Windows Update and see if there are any new USB drivers available.

 

Will go to Via to check it out. Both Computers have the Via. All updates for XP SP1 had been installed with the exception of two driver updates.
Every time I have downloaded the drivers MS found for previous operating systems (ME and 2000), its messed up the computers. Will try again.... Thanks for your quick response.

 

Thanks for your responses. Since it 'sees' the printer sometimes and then overnight... forgets its there (computers are always on) sometimes not, it'll be a little while before i know if my problem is cured. Will post back at that time. Thanks.