Hello, I have been googling this issue for a while now and searching these forums but have not found a solution. I have 4 computers all running Windows 7 64bit Ultimate. They have all been part of the same Homegroup for a while now and have worked fine. They all run the same Avast Free antivirus and Windows Firewall is OFF on all computers. They all have the same network and sharing settings. As of today though, the main computer that created the homegroup cannot see any other homegroup computers and none of the 3 other homegroup computers can see the main homegroup PC. Even if I leave the homegroup and then re-join, the homegroup wizard sees the main PC with the homegroup available to join, prompts me for password and joins, yet I still cannot see the main homegroup PC. Things I have tried. 1. Ran Homegroup troubleshooter on all 4 computers. 2. Turned off/on/off/on Network Discovery on all 4 computers 3. Left/joined/left/joined homegroup on all 4 computers 4. Left homegroup on main computer and recreated it, then rejoined with reaming 3 computers. 5. Stood on my head and tried all of the above while meditating. Also, I can ping the main homegroup PC and it can ping other PC's. The underlying issue is the mian homegroup PC that created the homegroup cannot see any other homegroup computers and none of those three can see that one. Any ideas? EDIT: I also tried eliminating the homegroup completely and just making all the PC's public, but it's the same result. The one "main" PC can't see any other computers on the network and they canoot see it.