I've been having this problem for a while now, and upgrading to windows 10 didn't help. Basically, my pc is perfectly fine with connecting to literally every other network in the world, but when it comes to my home wifi, it says it can't connect to it. Meanwhile, nobody else who has tried to connect has had this problem. What could this be? I have tried forgetting the network, restarting, resetting the network adapter and TCP/IP, all to no avail.
This could be a simple issue with either: 1. Wireless Encryption 2. Wireless Standards
Try disabling the wireless encryption temporary and see if you are able to connect. If you are, you may need to set the encryption standard to something like WEP which is insecure, however, you will have no choice since your device not be able to support newer standards like WPA2.
It is also possible that your router is using N only mode which could be an issue if your PC does not support this standard. Try checking your network settings.