I've got a real interesting situation. I have an existing web app that runs on a number of desktops fine. On a few desktops I see the following behavior: Upon clicking a link that opens up a new window (to another URL in the same domain) the IE window freezes and IE needs to be killed. This happens on IE 6 & 7. When using Fiddler I see NO traffic when clicking the link. When using IE HttpAnalyzer I see a request register but no response. If I change the MaxConnectionsPerServer registry setting to a higher value, e.g. 10 the problem goes away. Looking at netstat I dont see any abnormal connections. So I'm totally confused, the issue seems to be on the client side and seems to be related to IE not being able to make an additional socket connection to the server, but netstat doesn't show that. Ideas?