My PC only allows My External Hard Disk and iPhone to be connected?

Why the **** nothing else can connect but those two?!

I tried my PSP! My Flash memory, and a NEW Flash memory!

My PC can't find anything else, as if am not connecting anything anyway… = =

Please help me make my PC find every removable disk i connect like before <3!

You should reinstall USB driver or check the USB of your computer or use USB hub