Unknown PCs showing up in my network! What does it mean?

Reya, welcome to Sevenforums!

This thread has been marked "solved" for the other user, so people might not notice your problem for this old thread. But I will try to help you out best I can.

Most likely, you have not been hacked. You might have some form of malware, but hacking is completely different. Do check just in case you have malware. Update your antivirus scanner and do a "Full scan". If you are worried still about being infected, install malwarebytes free, which is excellent at detecting additional infections: Malwarebytes Anti-Malware 1.61 - TechSpot Downloads
If you are really worried, and you notice strange things happening to your computer, run this tool if you can to remove malware: What is Windows Defender Offline?

After that, go to Network Sharing Center (type its name into your start menu search bar), and click "Change advanced sharing settings" on the far left. Make sure you are listed under "Home" (it is the first title you should see near the top), and make sure "Password protected sharing" is on.


Here is some info that you may find useful:

1. People that are connected to your router (if you have one) may be visable to you. This may include other computers in the house, people you give your router password to, or people who connect without needing to enter a password. Make sure any router you have is password protected. If you do not know how to do this, this tutorial can help: Wireless Security: How To Protect Your Network - created by merkat106
   Note that a router is what is connected to your modem, which further is connected straight to the wall outlet via the network cable.
2. If you have "Network discovery" on (in advanced sharing settings), you will be able to see other nearby people who are also broadcasting their computers. This helps to find networks, but also makes your computer, and others, visable. However, if password protected sharing is on, they cannot connect to your computer without its password. Make sure your user account is password protected.

I hope I've answered your question. If you are still having trouble, or have any other questions, please let me know and I may have an answer. Take care :)