About a week ago, my voip softphone would no longer register any connections. I have more than one voip vendor, and I use just one softphone - Zoiper Biz. Suddenly none of them would register, i.e. connect to the server. I tried some diagnostics, and found that when Viscosity, my VPN client, is running, the voip does not work. With Viscosity turned off, and no VPN connected, the voip works again. So, I thought I had at least a lead to solving the problem. Then yesterday, I was able to use the voip when Viscosity is running, at least for some of my voip vendors. One of them still would not work. So now I'm back to square one . . . it's an intermittent problem. Does anybody have any ideas on why this is happening and how to fix it?