Unwanted computer in Network

Greetings,

First of all I apologize if someone has already postes this matter. I am new here. I am contacting you about a problem I recently noticed. Today when I opened windows explorer, under the Network tab I noticed a new unknown computer called VALI-PC. I do not have wireless internet, I have broadband connection. I do not know this computer and I did not add it. At first I thought some sort of virus did it. I have reinstalled Windows, thinking that it would solve the problem, yet the unknown computer is still there. I have tried flushing the dns from the command prompt and other similar tricks, rebooted my computer but it's still there. I would like to know how to block and remove this computer from the Network folder. Note that I am not part of any workgroup and I do not own a workgroup. Also I am using Windows 7 Ultimate. Thank you in advance, best regards.

Have you tried opening Network and Sharing Center and let it make a full system map (upper right)? Possibly if it shows up there, you might be able to get the properties to describe what it is.

I have a wireless print server that shows up and looks like a computer so it may be a different type of device.

I was wondering about hardware too. Do you have any type of video or audio streaming? What about virtual PC type software? Do any online gaming or use torrent sites? I tried Spotify music and discontinued it because it used your PC to stream and you had no control of that part.
Joe

This sounds like a legitimate security problem over your wireless network, assuming you have one. The reason I bring this up is because Windows automatically names a computer after the first name of the primary user account. You may very well have someone named "Vali", whose computer was named "Vali-PC", inadvertently, or even intentionally, connecting their computer to your wireless network. You will want to follow the suggestions listed above, but I would go a step further and run Start -> Search -> cmd.exe and execute the "net view" command. If you see a share called \\VALI-PC, you should know definitely that you have a foreign share on the Windows workgroup, connected to your Local Area Network (LAN). Even if you do not see anything under "net view", I would still recommend all of the following:

Immediately disable or change the password on your wireless router. This is fundamental in getting illegitimate devices off of the network, and you may be running without a password.

Consider disabling the Service Set Identifier (SSID) broadcast. This reduces the surface area for potential attackers, and does prevent your router from appearing on wireless network lists. You will need to manually input your wireless SSID when looking for your wireless router connections for the first time.

Consider instituting MAC address filtering over wireless, if supported by your router. Under this situation, you can tie in the unique MAC address of every network interface card (NIC) in your home or office, and automatically deny all other connection requests from foreign devices.

Please remember that these are suggestions that I am making based on the information you have posted thus far. Every situation is different, because I do not know how your network is configured: neither its size or scope.

"I do not own a workgroup"
Your assertion that you do not own a workgroup is false. You are simply on a workgroup called "WORKGROUP". This is the default name for any Windows computer that is connected to a router on a local area network. While the LAN forms the basis for an expansive layer that can support multiple networks, Windows automatically uses its own networking components to communicate with other Windows-compatible devices and computers using a narrowed workgroup layer for Windows networking. So, whether you realize it or not, every Windows 7 system is part of its own workgroup.