Downloading this assembly will create a different set of grants from other instances. (Exception from HRESULT: 0x80131401)

Question

We have SharePoint 2013 servers that have been fixed with Windows updates, and since then we have received the following error. We restarted the servers, manually uninstalled Windows updates, and then restarted the servers, restored a copy of the server window to the Windows update, but the error persists. We also deleted temporary files from the Windows directory, and nothing helps.

I added a screenshot of the Windows updates that were applied to our servers in one night

Loading this assembly would produce a different grant set from other instances. (Exception from HRESULT: 0x80131401) 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.IO.FileLoadException: Loading this assembly would produce a different grant set from other instances. (Exception from HRESULT: 0x80131401) Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [FileLoadException: Loading this assembly would produce a different grant set from other instances. (Exception from HRESULT: 0x80131401)] System.Linq.Enumerable.Any(IEnumerable`1 source) +0 System.Web.Compilation.BuildManager.GetPreStartInitMethodsFromAssemblyCollection(IEnumerable`1 assemblies, Boolean buildingFromCache) +210 System.Web.Compilation.BuildManager.CallPreStartInitMethods(String preStartInitListPath, Boolean& isRefAssemblyLoaded) +98 System.Web.Compilation.BuildManager.ExecutePreAppStart() +139 System.Web.Hosting.HostingEnvironment.Initialize(ApplicationManager appManager, IApplicationHost appHost, IConfigMapPathFactory configMapPathFactory, HostingEnvironmentParameters hostingParameters, PolicyLevel policyLevel, Exception appDomainCreationException) +1005 [HttpException (0x80004005): Loading this assembly would produce a different grant set from other instances. (Exception from HRESULT: 0x80131401)] System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +646 System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +159 System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +779 -------------------------------------------------------------------------------- Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.36366 

Answer 1

I came across the same exception when developing on Sitecore, and iisreset problem.

Answer 2

The solution is as follows:

Create a new DWORD registry value called LoaderOptimization and give it a value of 1 in the key "HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft.NETFramework".

Further reading:

http://blog.bugrapostaci.com/2017/02/08/loading-this-assembly-would-produce-a-different-grant-set-from-other-instances-exception-from-hresult-0x80131401/

https://social.technet.microsoft.com/Forums/en-US/5db05238-3c12-4e7e-af95-ca56545f0721/loading-this-assembly-would-produce-a-different-grant-set-from-other- instances? forum = sharepointgeneral

Answer 3

I was able to solve this problem by going to Bindings → Edit, then removing localhost as the host name of the site. Worked after that.