My Dell Inspiron 6400 has the Intel PRO/Wireless 3945ABG wireless network adapter in it. Prior to the upgrade to Windows Vista this was operating fine using the Intel PRO/Wireless utility software that installs with the driver.
After the Vista upgrade I activated the CPU/Memory utilisation gadget in the sidebar. Over a few days I noticed that the CPU utilisation was often quite high, and would never drop below 50%. I opened Task Manager and found that the process ZCfgSrv.exe was consuming 50% CPU at all times.
A little hunting around online and I found a notification on the Intel website that they are providing driver-only support for the 3945ABG adapter for Windows Vista at this time, and the Intel PRO/Wireless utility software is not compatible.
The solution I found was to remove the utility software but leave the driver installed. You can do this by opening Control Panel in Vista and choosing Uninstall a Program. Then highlight the Intel PROSet/Wireless entry in the list and choose Uninstall/Change
When the installer loads choose Modify and then Next. Unselect all installation options except for the Wireless LAN adapter driver (see screenshot), then click Modify.
This will remove the Intel PRO/Wireless utility software but leave the adapter driver intact. You can then simply use the Vista networking options to manage your wireless networking.