We have a machine running Vista Ultimate. According to the Network and Sharing Center, the computer is not connected to our wireless network. However, when you click Connect to a Network, it shows that it is connected to the wireless network. The computer can access the internet and print, so I know it is indeed connected to the network. However, it cannot "see" any other computers on the network (a combination of Vista and XP machines). If you manually type in a computer name it can connect to it, it just will not provide a list of computers on the network. Because it does not admit that it is connected to a network, I cannot turn on Network Discovery. I suspect that, once Vista realizes that it has a network connection again, it will re-enable itself.I have tried disconnecting and reconnecting from the wireless network from Connect to a Network. I have rebooted the computer and wireless router multiple times. None of the other Vista machines are having any problem seeing and connecting to the wireless network. I have also tried totally disabling the firewall, and I have checked to make sure that the workgroup is named correctly. All of our Vista machines already have autotuning disabled, because it interferes with other applications.Absolutely nothing changed on this machine or the wireless router. It just appears that Vista is refusing to admit that it has a network connection.Does anyone have any ideas about what is causing Vista to ignore its network connection?

Hello, 1. Remove and reinstall the Network adapter and upgrade the driver to the latest version. 2. Turn on Network Discovery and click Apply. (When you prompted, please enter password for the local administrator account in the User Account Control popup window). Repeat the above steps to turn on both File Sharing and Public folder sharing 3. In Network and Sharing Center, please click Diagnose and repair on the left, which should clear out some issues related to Networking. 4. Change the Computer name to test the issue. 5. Create accounts with the same user name and password on all computers. Login the account and have a test. If the problem persists, please answer the following questions for my further research. 1. Can this Vista computer ping and telnet the others properly? 2. What is the model of your computer as well as the wireless adapter? 3. Do you enable the DHCP on the wireless router and let the computers obtain the IP address automatically or set the static IP address for each computer? Good Luck!

Thanks for the response. I have already performed a system restore to a time before the computer started experiencing the issue, and that resolved it.