WOW no body replied!! I had thrown away my USB cable as I use Bluetooth dongle to connect my A925 to PC.. Anyways I've figured out how to Get rid of the Error "USB device not Recognised"
First of Go out and Buy a Genuine USB Port Extender Cable, and then plug your Phone into it and connect that NEW USB Port extender cable to the PC then It'll Show YOU new Hardware Found Message!! "It'll not show USB Device not Recognised" then Put in the A925 CD and Install the Software Manually
Select the Driver " CDROM:\Drivers\USB\Win2K_XP\USBMOT2000.INF"
then It'll show "Motorola USB Modem" is successfully installed!
now Install the Desktop soot and re-start the computer and Connect your A925 to PC Via Desktop suite which is in your Phone.... it'll Show USB COM4 again in the Mrouter!!!
VOILA your A925 Connects to PC again through USB after 2 years!