I'm selling my computer. My laptop is currently setup to automatically connect to my wireless home internet router every time it boots up. So obviously, somewhere on the laptop is stored the WPA-PSK key that is needed to access my secured password-protected wireless internet connection. But where? How to remove it? If it sell the laptop to my neighbor, I don't want them to automatically connect to my internet.
The operating system is Windows Vista.
Simply log into your router and change the WPA-PSK key to something else. If you're still worried reset you laptop to manufacturer defaults. (Using the recovery partition if there is one and basically putting everything back to the way it was when you bought it)
Yes, that is sensible advice setting the machine back to Factory defaults since it won't just be your connection settings you'll need to remove. You'll have other personal documents and private data lurking on the machine most likely you wouldn't want you neighbours to view, e.g. browsing history, photos, word processor documents, etc. Deleting the wireless profile would be a first starting step.
I found how to remove the WPA key: Control Panel -> Network and Internet -> Network and Sharing Center -> Manage Wireless networks. Then select the network and click delete.
You should really reformat it back to factory defaults -- what if you forgot something else?
Yup reformat it so you don't have other sensible documents to be discovered by the buyer.
Always do this if possible. Restore from the CDs or Recovery partition. If you don't have a valid windows license to go with it, then just wipe the drive with Boot And Nuke or DBAN (found on the UBCD) and let the buyer purchase a valid license/CD (but let them know they'll have to do that!)