I have two unknown computers that are showing up on my network. I have blocked the IP address of one of them, but the other does not list an IP in the details, so I am unable to add it to the block list. Even though I have blocked the one, and I am using a WPA encrypted wireless router, these two computers keep showing up active. How can I get them off my network?
If you can't see the IP address of the second computer, you must be able to see its name on the network map (or the IP on the network map). Open the command prompt, try the ping command using the PCs name, and see if you're able to get the IP.
A better solution would be to change the WPA passphrase, and then check if these devices are still online. If they are, they may actually turn out to be something pretty harmless, like a set top box, a printer, or a remote network share.