Quartus 7.2 not detecting USB blaster from windows 7 !!

Can you please help me out..

My USB Blaster is not shown in programmer window
I'm using Quartus 7.2 DE2 kit
OS : windows-7 32 bit..

I installed the driver from drivers/usb-blaster of quartus folder
whenever i plugin usb, device manager shows as Altera USB Blaster, and when I UPDATE Driver software it says device is up to date !!!!
everything looks fine... but my programmer does not recognize usb blaster...
I tried every single options running programmer in windows 7 compatability mode....
....installing even 13.1 quartus...but no luck...

Thank you.