Adhoc Networking

I am running Vista 64 Ultimate Edition and I connect to the internet through a 20mb cable connection.

I do not have a router at present but I have a wireless adapter on my pc that I want to use to set up an adhoc network for both my wireless laptop and my nintendo wii. Is this possible and how? I've made a few attempts and can get both devices to see my network but I can never successfully connect. I've also tried bridging the wireless adapter to my network with no success.

I don't really know what I am doing.

Any help would be greatly appreciated.

Could you tell us what you do have? I'm a little confused. Do you have a wireless cable modem? Could it be wired?

I have a wired cable modem, a wireless card in the pc connected to nothing at the moment. I used to host an adhoc network on it under XP and my laptop, Wii and PSP could connect to that. Just having trouble acheiving the same in Vista now.

Hmmm...I can't think of any obvious solutions. Could it be an administrative privileges problem?