My friend's Windows 7 x64 ultimate machine recognizes some USB flash drives but not some other ones. The types of all are USB2 and also all drivers are installed (device manager). I don't know what is the problem. Is there any idea please?
Also I read that link. I found something,
In the Universal Serial Bus controllers (device manager), I found the name of that USB flash drive. On the properties of it and in the Device status there is the following message:
No divers are installed for this device.
Now how to install that driver please?
And this is an image from that flash drive (silicon-Power 4g).