After upgrading Episerver to 11.3.2, I get the following TypeLoadException:

Server Error in '/' Application.
Could not load type 'EPiServer.PlugIn.GuiPlugInAttribute' from assembly 'EPiServer, Version=11.3.2.0, Culture=neutral, PublicKeyToken=8fe83dea738b45b7'.
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.TypeLoadException: Could not load type 'EPiServer.PlugIn.GuiPlugInAttribute' from assembly 'EPiServer, Version=11.3.2.0, Culture=neutral, PublicKeyToken=8fe83dea738b45b7'.

Source Error: 


[No relevant source lines]

Source File: c:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files\root\28edaa5b\7a59bc51\App_global.asax.mjdpz7zo.0.cs    Line: 0 

Stack Trace: 


[TypeLoadException: Could not load type 'EPiServer.PlugIn.GuiPlugInAttribute' from assembly 'EPiServer, Version=11.3.2.0, Culture=neutral, PublicKeyToken=8fe83dea738b45b7'.]
   EPiServer.Framework.Initialization.InitializationModule.EngineExecute(HostType hostType, Action`1 engineAction) +1390
   EPiServer.Framework.Initialization.InitializationModule.FrameworkInitialization(HostType hostType) +225
   EPiServer.Global..ctor() +103
   XXX.Global..ctor() +37
   ASP.global_asax..ctor() in c:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files\root\28edaa5b\7a59bc51\App_global.asax.mjdpz7zo.0.cs:0

[TargetInvocationException: Exception has been thrown by the target of an invocation.]
   System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck) +0
   System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) +142
   System.Activator.CreateInstance(Type type, Boolean nonPublic) +105
   System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, StackCrawlMark& stackMark) +1515
   System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes) +186
   System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture) +27
   System.Web.HttpRuntime.CreateNonPublicInstance(Type type, Object[] args) +80
   System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context) +310
   System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext) +369

[HttpException (0x80004005): Exception has been thrown by the target of an invocation.]
   System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +534
   System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +111
   System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +718

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.7.2558.0

I have upgraded all add-ons to be compliant with Episerver 11.

Has anyone else any experience on fixing this error?

Thanks!