i am having problems installing EW-7612UAn driver on my windows 7 64bit OS. when i inserted the USB EW-7612UAn, nothing happens, it does not install. when i manually installed the driver, it says device driver software was not successfully installed. The same thing happened on my laptop when i inserted the usb EW-7612UAn. it worked fine before but now something went wrong and won't install. i tried using system restore but to no avail. please help. thank you