Running the 64 bit version of IIS Express 8 RC with Visual Studio 2010

Question

I have a web app that uses the 64 bit version of SharpSvn, a managed DLL with an unmanaged dependency. It will not run in IIS Express 7.0. Switching to the 32 bit version of the assembly works fine.

I installed the 64 bit version of IIS 8 RC. However Visual Studio 2010 launches the 32 bit version of IIS Express.

.

I can launch the 64 bit version of IIS manually with the following command:

"C:\Program Files\IIS Express\iisexpress.exe"  /config:"C:\Users\zippy\Documents\IISExpress\config\applicationhost.config"  /site:"MrDVCS" /apppool:"Clr4IntegratedAppPool"

In my WebProject.csproj The relevant XML seems to be <UseIISExpress>true</UseIISExpress>. If I edit the file in Visual Studio, the Intellisense does not offer a similar named tag for 64 bit, and it does not offer me an attribute.

So how do I get Visual Studio to launch the 64 bit version of IIS Express RC?

Answer 1

I have been trying to do the same thing, but can't seem to find how to launch IIS Express in 64 bit mode.
The only way that I can find to debug in 64 bit mode is the following:
Start IIS Express as you have above (in 64 bit mode).
In your Visual Studio project Properties, switch the servers to specify "Use Custom Web Server", and put in a url.
Go to debug | Attach to process, and then select your running IISExpress instance.
Place a breakpoint, and debug in 64 bit mode.
Have fun,

Answer 2

This is for VS 2012. Check for 2010 whether it works.

Add the registry key. Go to

HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\11.0\WebProjects

Add new key of type “DWORD (32-bit) Value”

Name: Use64BitIISExpress Value: 1

However, this feature is not supported and has not been fully tested by Microsoft

Reference: http://visualstudio.uservoice.com/forums/121579-visual-studio/suggestions/3254745-allow-for-iis-express-64-bit-to-run-from-visual-st

Answer 3

As Santhosh points out you can set the registry key

HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\11.0\WebProjects

Add new key of type “DWORD (32-bit) Value”

Name: Use64BitIISExpress Value: 1

However, make sure to delete or rename the IISExpress directory under your My Documents folder.

That's what got the registry key to work for me, it seems that IISExpress config files which are created on first launch are different between the x86 and x64 versions.