SYMPTOMS
When opening ASP.NET web application internal server error 500 appears: "%1 is not a valid Win32 application."
CAUSE
IIS is in 32bit mode, while x64 .NET framework is registered.
SOLUTION
Change IIS to x64 mode and register x64 ASP.NET again:
1. Run
cscript %SYSTEMDRIVE%\inetpub\adminscripts\adsutil.vbs SET W3SVC/AppPools/Enable32bitAppOnWin64 0
2. Run
%SYSTEMROOT%\Microsoft.NET\Framework64\v2.0.50727\aspnet_regiis.exe -i
MORE INFORMATION
For more information on IIS modes and switchings:
http://support.microsoft.com/kb/894435
APPLIES TO
AxCMS.net versions: All versions
IIS versions: 5.x, 6.0