i have two USB2 ports on the rear of my PC, i have two scanners(one self powered), a modem and a multi card reader i would like to connect. at the moment i am using a 4 into 1 non pwered usb adapter. However, the two scanners will not work if they are both plugged into the adapter, the error message i usually get is cannot open a twain scource and then cannot communicate with the device. Has anyone got any advice to help me overcome this problem, or could i buy a POWERED USB HUB and would it overcome this problem?

I don't know if trying to connect 2 scanners and trying to operate them both at the same time is a good idea. I personally wouldn't try it. Does it work with just the single scanner? Is the drivers for the scanners installed? I think it is the 2 scanners on at once may be the problem.
I recall in the early days of USB that connecting even 2 USB devices eg scanner and external CDRW was a bit resource consuming and was not recommended.

i may have confused you, i only want them connected at the same time, i dont want to use them at the same time, i just have a problem with the hub i think! any ideas ???