Wrong assembly version from Owin dependency

I need to switch a specific library that was from version 16.1 before to version 15.0. I did this by removing the higher version and installing the lower version by nuget.

When building, the correct dll (15.0) is created in the bin-directory. But I receive the following error when starting the (web) application:

    [FileLoadException: Could not load file or assembly 'Microsoft.SharePoint.Client.Runtime, Version=16.1.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)]
   System.ModuleHandle.ResolveType(RuntimeModule module, Int32 typeToken, IntPtr* typeInstArgs, Int32 typeInstCount, IntPtr* methodInstArgs, Int32 methodInstCount, ObjectHandleOnStack type) +0
   System.ModuleHandle.ResolveTypeHandleInternal(RuntimeModule module, Int32 typeToken, RuntimeTypeHandle[] typeInstantiationContext, RuntimeTypeHandle[] methodInstantiationContext) +145
   System.Reflection.RuntimeModule.ResolveType(Int32 metadataToken, Type[] genericTypeArguments, Type[] genericMethodArguments) +158
   System.Reflection.CustomAttribute.FilterCustomAttributeRecord(CustomAttributeRecord caRecord, MetadataImport scope, Assembly& lastAptcaOkAssembly, RuntimeModule decoratedModule, MetadataToken decoratedToken, RuntimeType attributeFilterType, Boolean mustBeInheritable, Object[] attributes, IList derivedAttributes, RuntimeType& attributeType, IRuntimeMethodInfo& ctor, Boolean& ctorHasParameters, Boolean& isVarArg) +91
   System.Reflection.CustomAttribute.GetCustomAttributes(RuntimeModule decoratedModule, Int32 decoratedMetadataToken, Int32 pcaCount, RuntimeType attributeFilterType, Boolean mustBeInheritable, IList derivedAttributes, Boolean isDecoratedTargetSecurityTransparent) +438
   System.Reflection.CustomAttribute.GetCustomAttributes(RuntimeAssembly assembly, RuntimeType caType) +103
   System.Reflection.RuntimeAssembly.GetCustomAttributes(Boolean inherit) +37
   Owin.Loader.DefaultLoader.SearchForStartupAttribute(String friendlyName, IList`1 errors, Boolean& conflict) +106
   Owin.Loader.DefaultLoader.GetDefaultConfiguration(String friendlyName, IList`1 errors) +46
   Owin.Loader.DefaultLoader.LoadImplementation(String startupName, IList`1 errorDetails) +75
   Owin.Loader.DefaultLoader.Load(String startupName, IList`1 errorDetails) +21
   Microsoft.Owin.Host.SystemWeb.OwinBuilder.GetAppStartup() +115
   Microsoft.Owin.Host.SystemWeb.OwinHttpModule.InitializeBlueprint() +28
   System.Threading.LazyInitializer.EnsureInitializedCore(T& target, Boolean& initialized, Object& syncLock, Func`1 valueFactory) +115
   Microsoft.Owin.Host.SystemWeb.OwinHttpModule.Init(HttpApplication context) +106
   System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers) +534
   System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context) +172
   System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context) +352
   System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext) +296

What is most irritating about this error is that the Owin-package seems to cause this error. But Owin should not have a reference to Microsoft.SharePoint.Client at all according to the NuGet-documentation.

Or is this whole strack trace misleading and Owin does not have to do anything with this problem?

I encountered the same problem.

For me the problem got solved by removing the .dll that was causing the error from the bin directory. (In my case it was Microsoft.Online.Sharepoint.Tentant.dll)