Q: Why can't I connect my PC to my iPhone's Personal Hotspot?

I cannot connect my PC to my iPhone's personal hotspot through Wifi and even through USB. When I try to connect through wifi using my USB wifi adapter it shows in the available networks. I try to connect, put the security key it just says its unable to connect. When I try to connect through USB it doesn't even show on the available networks, can anyone help me with this?