Error opening IAS Web interface: "Loading this assembly would produce a different grant set from other instances. (Exception from HRESULT: 0x80131401)"

Applies to

Imagicle Application Suite 2016.Summer.1 and later.

On IAS server, Microsoft System Center Operations Manager 2016 Agent is installed.

Description

The following error is shown when trying to open Application Suite Web interface:

"Loading this assembly would produce a different grant set from other instances. (Exception from HRESULT: 0x80131401)"

Moreover, in Windows Event Registry, there are the following two events in Application section:

1. Source:        .NET Runtime
   Event ID:      1022
   Level:         Information
   User:          IIS APPPOOL\DefaultAppPool
   Description:
   .NET Runtime version 4.0.30319.36440 - The profiler was loaded successfully.  Profiler CLSID: '{AD5651A8-B5C8-46ca-A11B-E82AEC2B8E78}'.  Process ID (decimal): 7728.  Message ID: [0x2507].

2. Source:        ASP.NET 4.0.30319.0
   Event ID:      1309
   Level:         Warning
   Description:
   Event code: 3005 
   Event message: An unhandled exception has occurred. 
   Event time: 28-06-2018 12:29:28 
   Event time (UTC): 28-06-2018 10:29:28 
   Event ID: 5b590a7766b241d087b6e894b6181c5b 
   Event sequence: 1 
   Event occurrence: 1 
   Event detail code: 0 
    
   Application information: 
       Application domain: /LM/W3SVC/1/ROOT/fw-1-131746553661044212 
       Trust level: Full 
       Application Virtual Path: /fw 
       Application Path: C:\Program Files (x86)\StonevoiceAS\ 
       Machine name: EGCLINEAFAXSV01 
    
   Process information: 
       Process ID: 8956 
       Process name: w3wp.exe 
       Account name: NT AUTHORITY\SYSTEM 
    
   Exception information: 
       Exception type: FileLoadException 
       Exception message: Loading this assembly would produce a different grant set from other instances. (Exception from HRESULT: 0x80131401)
      at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source)
      at System.Web.Compilation.BuildManager.GetPreStartInitMethodsFromAssemblyCollection(IEnumerable`1 assemblies, Boolean buildingFromCache)
      at System.Web.Compilation.BuildManager.GetPreStartInitMethodsFromReferencedAssemblies()
      at System.Web.Compilation.BuildManager.CallPreStartInitMethods(String preStartInitListPath, Boolean& isRefAssemblyLoaded)
      at System.Web.Compilation.BuildManager.ExecutePreAppStart()
      at System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager appManager, IApplicationHost appHost, IConfigMapPathFactory configMapPathFactory, HostingEnvironmentParameters hostingParameters, PolicyLevel policyLevel, Exception appDomainCreationException)

    
   Request information: 
       Request URL: http://localhost/fw/ 
       Request path: /fw/ 
       User host address: ::1 
       User:  
       Is authenticated: False 
       Authentication Type:  
       Thread account name: NT AUTHORITY\SYSTEM 
    
   Thread information: 
       Thread ID: 3 
       Thread account name: NT AUTHORITY\SYSTEM 
       Is impersonating: False 
       Stack trace:    at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source)
      at System.Web.Compilation.BuildManager.GetPreStartInitMethodsFromAssemblyCollection(IEnumerable`1 assemblies, Boolean buildingFromCache)
      at System.Web.Compilation.BuildManager.GetPreStartInitMethodsFromReferencedAssemblies()
      at System.Web.Compilation.BuildManager.CallPreStartInitMethods(String preStartInitListPath, Boolean& isRefAssemblyLoaded)
      at System.Web.Compilation.BuildManager.ExecutePreAppStart()
      at System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager appManager, IApplicationHost appHost, IConfigMapPathFactory configMapPathFactory, HostingEnvironmentParameters hostingParameters, PolicyLevel policyLevel, Exception appDomainCreationException)
    

Cause

The root cause is the APM component of Microsoft System Center Operations Manager 2016 Agent.

Solution

As explained by this article from Microsoft, the issue can be fixed:

• If APM feature is required on that server: downgrade SCOM Agent to 2012 R2 and continue monitoring;
• If APM feature is not required on that server: either uninstall SCOM 2016 Agent completely, or re-install it with “NOAPM=1” in the setup command line

To uninstall SCOM 2016, please open Windows Control Panel and select "Programs and features". Locate the application called "Microsoft Monitoring Agent" and click "Uninstall".

Once done, please reboot the server.