WiFi Ad hoc connection setup for windows Vista

Follow the steps given below...

1. Click the Start Button and select Control Panel.
2. Select Network and Internet. (If Control Panel is in Classic View, skip this step)
3. Open Network and Sharing Center.
4. Select Set up a connection or network (in the left pane).
5. In the resulting window, select Set up a wireless ad hoc (computer-to-computer) network.
6. Click Next and again on the following page.
7. In the Network name textbox, input a name for the network.
8. Select a security type from the dropdown. (If you select WEP, you will need to enter a security key in the unghosted textbox)
9. If you want to use this network more than once, check the Save this network checkbox, if you only need it for a one time fix, leave the checkbox unchecked.
10. Click Next.
11. Click Close.
Your network is now created and can be accessed by other computers in the same manner as connecting to a regular wireless connection. If you utilized WEP, then you will need to give them the security key. If you did not opt to save the network during creation, it will be deleted when everyone has disconnected from it.