Can’t connect to my network connection anymore.

I am using an Acer Aspire 5735z Laptop. Atheros AR5B91 Wireless Adapter. I had my laptop formatted 3 weeks ago because i was facing problems and all of them vanished after formatting. I’m facing a slight problem at the moment and it’s that i cant connect to my home internet connection anymore, every time i try to connect i get a “Windows cannot connect” msg. But I can connect to some other networks and all of them have a 802.11n Radio Signal. My home’s has 802.11b/g. I made sure that i was typing the security key right (WPA-PSK Security Type). I can’t seem to figure out the solution. Can anyone help. I can connect using LAN but it’s annoying when i have to move. Plzzzzzz Help