Mutex could not be created. 
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.InvalidOperationException: Mutex could not be created.  

[InvalidOperationException: Mutex could not be created.]
   System.Web.Compilation.CompilationMutex..ctor(String name, String comment) + 3464673 
   System.Web.Compilation.CompilationLock..cctor() + 158 

[TypeInitializationException: The type initializer for 'System.Web.Compilation.CompilationLock' threw an exception.]
   System.Web.Compilation.CompilationLock.GetLock(Boolean& gotLock) + 32 
   System.Web.Compilation.BuildManager.EnsureTopLevelFilesCompiled() + 114 

[HttpException (0x80004005): The type initializer for 'System.Web.Compilation.CompilationLock' threw an exception.]
   System.Web.HttpRuntime.FirstRequestInit(HttpContext context) + 3426855 
   System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) + 88 
   System.Web.HttpRuntime.ProcessRequestInternal(HttpWorkerRequest wr) + 149