|USB devices often will not work properly when plugged into certain USB ports. |
See response 3 in this:
E.g. if you plug the mouse into a port directly connected to the laptop's mboard you may not have the problem.
The ACPI support of your mboard, which includes support for Standby and Hibernate modes, may not work properly if you have re-loaded Windows from scratch using a regular Windows CD but did not install the main chipset drivers.
Whenever you load Windows from a regular Windows CD (or DVD) from scratch, after Setup is finished you must load the drivers for the mboard, particularly the main chipset drivers, in order for Windows to have the proper drivers for and information about your mboard hardware, including it's AGP or PCI-E, ACPI, USB 2.0 if it has it, and hard drive controller support. If you have a generic system and have the CD that came with the mboard, all the necessary drivers are on it. If you load drivers from the web, brand name system builders and mboard makers often DO NOT have the main chipset drivers listed in the downloads for your model - in that case you must go to the maker of the main chipset's web site, get the drivers, and load them.
There may be some setting in the mboard's bios Setup you need to enable so that a USB mouse can "wake up" the computer after it goes into Standby mode.