New Insipiron N7010 Wireless Network Connection Issue

We currently have a problem when we connect to our home network with this laptop. 3 other other laptops can connect with varying strength levels from anywhere in the house. This one cannot connect from the rear rooms or main bedroom. Even sitting in the room where the modem is, the strength varies from dropout to 4 even when the others have not altered strength? What's the issue???? Any help would be great.

Thanks

ACDCTC