I've noticed that when using asp.net 2.0 dev server that the trace would only show up on one or two pages. I decided to do some research into it and found out it has to do with the trace section of webconfig. There is a attribute called requestLimit whose limit was set to 20. After 20 requests the trace just stops showing up. 20 requests may not sound that bad but with the dev server all requests (including images and everything) go through the asp.net runtime so one page with my website would have 20 requests for other resources. I found out that there is another attribute called mostRecent which when set to true will discard older requests rather than stop working. I also didn't read the note in the webconfig about "you can view the application trace log by browsing the "trace.axd" page from your web application root".