Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.Hosting.HostingEnvironmentException: Failed to access IIS metabase.

The process account used to run ASP.NET must have read access to the IIS metabase (e.g. IIS://servername/W3SVC). For information on modifying metabase permissions, please see http://support.microsoft.com/?kbid=267904.

[HostingEnvironmentException: Failed to access IIS metabase.]
System.Web.Configuration.MetabaseServerConfig.MapPathCaching(String siteID, VirtualPath path) +637
System.Web.Configuration.MetabaseServerConfig.System.Web.Configuration.IConfigMapPath2.MapPath(String siteID, VirtualPath vpath) +9
System.Web.Hosting.HostingEnvironment.MapPathActual(VirtualPath virtualPath, Boolean permitNull) +174
System.Web.Hosting.HostingEnvironment.MapPathInternal(VirtualPath virtualPath, Boolean permitNull) +51
System.Web.CachedPathData.GetConfigPathData(String configPath) +341
System.Web.CachedPathData.GetConfigPathData(String configPath) +234
System.Web.CachedPathData.GetApplicationPathData() +38
System.Web.CachedPathData.GetVirtualPathData(VirtualPath virtualPath, Boolean permitPathsOutsideApp) +8806383
System.Web.Configuration.RuntimeConfig.GetLKGRuntimeConfig(VirtualPath path) +117


Solution:
Just run this command
c:\windows\Microsoft.NET\Framework\v2.0.50727>aspnet_regiis -i

More Info
http://support.microsoft.com/?kbid=267904 http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=116989&SiteID=1
http://support.microsoft.com/kb/555583