If you are loading Linksys QuickVPN Client onto a WIndows XP Pro SP2 PC, and use the default software Windows Firewall, and you want to leave it on all the time especially when running the QuickVPN client, then you need to take some steps. 1. Verify that your problem is solved by turning off the WIndows firewall. 2. If you can connect with the firewall off, then turn on the firewall and Install the MS Patch. http://support.microsoft.com/kb/889527/en-us 3. Restart the computer. 4. Add the Linksys QuickVPN Client to the Windows Firewall Program Exceptions. 5. Add the Linksys QuickVPN Client to the startup folder for ease of use. 6. Verify that your problem is solved by connecting with the QuickVPN client.