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Last post Aug 01, 2007 06:33 PM by JasonBSteele
Jul 29, 2007 07:22 PM|LINK
When I tried to debug an ASP.NET web application assembly (with almost no content, thus running fine) on the new beta 2 using the ISS web server, I got the following error message (independent of the assembly being strongly or weakly named):
"Unable to start debugging on the web server. Strong name validation failed"
Is anyone aware of a workaround for this one?
Aug 01, 2007 01:07 PM|LINK
This fixed the problem for me. The complete article can be found at
When a Web project is run on Windows Vista, it may fail to start and the following error may be shown: "Unable to start debugging on the web server. Strong name validation failed. Click Help for more information."
To resolve this issue:
Disable strong name validation for a Visual Studio file (iisresolver.dll) by doing the following:
1. Click on Start, All Programs, Accessories, Command Prompt, and then select Run as administrator
2. You may see the screen grey and a 'User Account Control' dialog box appear. If this happens, click Continue so that the command prompt starts.
3. Obtain a copy of sn.exe. Sn.exe installed with Visual Studio 2005, and the .NET Framework 2.0 SDK, and therefore it may already be on the computer. If it is not on the computer, then download .NET Framework
2.0 SDK to obtain it. The x86 version of the Software development kit can be downloaded from
The x64 version of the SDK can be downloaded from http://www.microsoft.com/downloads/details.aspx?FamilyId=1AEF6FCE-6E06-4B66-AFE4-9AAD3C835D3D.
4. Run one of the following commands, as appropriate:
"<path_to_sn>\sn.exe" -Vr "%ProgramFiles%\Microsoft Visual Studio 9.0\Common7\IDE\iisresolver.dll"
"<path_to_sn>\sn.exe" -Vr "%ProgramFiles(x86)%\Microsoft Visual Studio 9.0\Common7\IDE\iisresolver.dll"
This assumes that Visual Studio was installed to the default location. If Visual Studio was installed to a custom location, then '%ProgramFiles%\Microsoft Visual Studio 9.0' should be replaced with the path
where Visual Studio was installed.
vS2008 Orcas Vista "Strong Naming Error"
Aug 01, 2007 03:44 PM|LINK
That solved it, thanks!
Aug 01, 2007 06:33 PM|LINK
I got this as well - it seems to affect Vista. I found this
http://download.microsoft.com/download/d/d/1/dd18043a-fe86-4f57-ac22-791b30e6f04b/ExpressReadme.htm which solved it. Search for "Strong Name" in the doc and read the section. Basically you need to Run as Admistrator the "Visual Studio 2008 Beta 2 Command
Prompt" from yiour Start Menu. then paste this in:
sn -Vr "%ProgramFiles%\Microsoft Visual Studio 9.0\Common7\IDE\iisresolver.dll"
It marks the IIS Resolver application as not requiring string name verification.