We've experienced two weird issues using Microsoft Visual Studio 2005 on Windows Vista. Both are connected to developing web applications using ASP.NET and the Web Server which comes integrated into the IDE.

First thing is, that the localhost is not any more localhost. Due to the IPv6 mapping
in file c:/windows/system32/drivers/etc/hosts which looks like this

::1             localhost

it seems, that request from http://localhost:1111 (number varies) never hit the WebDev.exe. Commenting this line out using

#::1             localhost

overcomes this problem (unless you need IPv6 it probably won't be a problem).

Second issue was the already mentioned port number. When you hit the Start debugging button, Visual Studio launched Web server and automatically opened your favorite browser on that page. But in our case, the URL in browser contained different port number that the Web server has been running on. After some digging I have found this solution.