Wireless Problem

I’m have my MacBook Airv(OS X 10.9.2 connecting to the Internet via my wireless network which is operated through AirPort Express (5th Generation) 802.11n.)router. I’m trying to get my HP with Windows 7and a 2.40GHz Intel Core i3-370M processor and 802.11 b/g/n Wireless to connect to my wireless network but it says it cannot. The diagnostic program cannot resolve it either. The HP does connect to my neighbors unsecured network and I didn’t have any trouble with my old router/network. I installed Airport Utility on the HP but that didn’t solve the problem either. Does anybody have any solutions?

Add your HP's MAC Address to list on your router. Also check to see if router firfewall is blocking new connections.

What method of encryption are you using?

WPA2 Personal for the network & AVG on the HP computer. The crazy thing is that I decided to set up a secured guest network and the Windows 7 connected to that but I still can't connect to the other one.

Thanks for your reply. I'm new to Apple and Airport Express and as a result do not know how to comply with either of your suggestions.

I don't think that AVG is blocking you but it is worth a try to disable it while trying to connect with your HP. Since you are able to connect to the guest network that eliminates it being a problem with the AirPort Express.