Visual Studio 2008 Internal Web Server stopped working in Vista

I have been debugging perfectly fine using Visual Studio 2008 using visual studio internal web server, but suddenly today it stopped working (maybe due to windows update, but still not sure about the cause of this suddenly not working), On starting the debugger IE came up with a blank page saying the page could not be opened, same happened in firefox when I tried to use that for debugging, It took me sometime to realize that this was due to a vista Issue, IPv6 gets installed with Vista and cannot be un-installed or disabled easily, and that creates the problem. I followed this post to sort out my issue.

The main action that sorted this out for me was to edit the hosts file in C:\Windows\System32\drivers\etc

and change the localhost entry from

::1             localhost


:::1             localhost

one more Collen.

So if you are having this issue as well, do not pull your hair out but follow the post linked above or change your host file entry for localhost as explained above.

Install an Assembly into the Global Assembly Cache

On Windoze one can install assembles into Global assembly cache to make assembly accessible from everywhere on the machine, there are four main ways to install assembly into global assembly cache , but the one that I found to be the easiest and available by default on windows is the Assembly Cache Viewer (Shfusion.dll) , using this method one can use windows explorer to drag the assembly file into the global cache folder at windows\assembly however this method requires that the assembly is strongly typed, in order to do that one has to sign the assembly, In Visual studio this can be done by click on the class library project properties and select Signing tab and then selecting Sign the assembly.

Note: On Windows Vista I was getting Access denied message on trying to use Assembly Cache Viewer although I was performing the copy using Administrative rights, and ended up using .NET Framework Configuration Tool (Mscorcfg.msc) which worked like a charm for me. So if you are getting the same issue better try using the alternate ways of installing the assembly . AJAX stops working on upgrade from 2.0 to 3.5


I upgraded my existing project developed in and .net extensions 1.0 to Ajax extensions that come bundled with 3.5 using Visual Studio 2008. After the upgrade I got compiler errors saying that the required assembly could not be found.


It turns out that on conversion Visual studio does not remove the reference to the AJAX extension for version 1.06 and hence the error.


In order to sort out this issue you need to go into project properties -> Reference tab and remove the reference System.Web.Extensions and create a new reference to the System.Web.Extension for the .net 3.5 dll located at \Program Files\Reference Assemblies\Microsoft\Framework\v3.5

alternately after removing the reference you can copy System.Web.Extensions.dll from from the 3.5 version to the bin directory of your project to sort out the issue.

Please note that if your project has any reference to the old System.Web.Extensions it will complain that there are two reference to System.Web.Extensions, in this case you can either remove older version of extensions from your system and deleted all temporary files in Windows temp and restart Visual Studio 2008, alternately make sure that all references to System.Web.Extensions to the older version are removed from your project.

For more details of how to upgrade project from .net 2 to .net 3.5 check out this post

Visual Web Developer blog

Happy Coding 🙂