Windows 7 Hibernate/Resume Problem

I am having a problem with Windows 7 Pro x64. When I hibernate the PC and then resume windows no USB devices work (9 out 10 times), no usb mouse though the mouse pointer is visible, the USB W/lan dongle won't work nor a USB pen drive plugged in is not recognised. I have to shut down the PC and restart.

I have noted that if I hibernate the PC and leave the mains power switched on, when I resume windows the USB devices work. If I hibernate the PC, switching off the mains power, when I resume windows the USB devices don't work. This can be intermittent as the odd time they do work.

When no USB devices work device manager does not list any 'Human Interface Devices', 'Mice and other Pointing devices' and under USB controllers - generic hub - Power tab - the mouse nor USB W/lan are not listed. When they work all these are listed fine.

PC spec is Asus P7H55D-M Evo M/board, Intel i5 660 CPU, 4GB Ram.

I hope someone can tell me what may be causing this annoying problem.

Device Manager - USB Root Hub - could you check the Power Management tab and uncheck 'Allow the computer to turn off this device...'

have you checked the bios settings relating to usb?

Thanks for the suggestions.

However Unchecking the 'allow computer to turn off this device' makes no difference.

Have checked BIOS settings relating to USB and seem ok but is there something specific I should be looking for?