Hi all,
Here my situation : I have Exchange server CU23 (CAS + Mailbox roles) , OS : Windows server 2008 R2 SP1 enterprise , with 2 partitions
C: installed Exchange
D: for mailbox databases store
Recently, I have to repair my Exchange server by:
- Format partition C and reinstall Windows OS (Windows server 2008 R2 SP1 enterprise)
- Prepare Exchange 2013 prerequisites by following : https://docs.microsoft.com/en-us/exchange/exchange-2013-prerequisites-exchange-2013-help
- Install Exchange 2013 CU23 in recover mode : setup /m:recoverserver /iacceptexchangeserverlicenseterms
After restart, everything works fine except Exchange Toolbox (I can use Exchange powershell)
This is error when I try to open Exchange Toolbox

Could not load file or assembly 'Microsoft.Exchange.Management.SnapIn.Esm, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. This assembly is built by a runtime newer than the currently loaded runtime and cannot be loaded.
at System.Reflection.Assembly._nLoad(AssemblyName fileName, String codeBase, Evidence assemblySecurity, Assembly locationHint, StackCrawlMark& stackMark, Boolean throwOnFileNotFound, Boolean forIntrospection)
at System.Reflection.Assembly.InternalLoad(AssemblyName assemblyRef, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection)
at System.Reflection.Assembly.InternalLoad(String assemblyString, Evidence assemblySecurity, StackCrawlMark& stackMark, Boolean forIntrospection)
at System.Activator.CreateInstance(String assemblyName, String typeName, Boolean ignoreCase, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, Evidence securityInfo, StackCrawlMark& stackMark)
at System.Activator.CreateInstance(String assemblyName, String typeName)
at System.AppDomain.CreateInstanceAndUnwrap(String assemblyName, String typeName)
at Microsoft.ManagementConsole.Internal.SnapInClient.CreateSnapIn(String assemblyName, String typeName)
at Microsoft.ManagementConsole.Internal.ClassLibraryServices.Microsoft.ManagementConsole.Internal.IClassLibraryServices.CreateSnapIn(String assemblyName, String typeName)
at Microsoft.ManagementConsole.Executive.SnapInInitializationOperation.OnStart()
at Microsoft.ManagementConsole.Executive.RunningOperationsTable.EnqueueOperation(Operation operation)
at Microsoft.ManagementConsole.Executive.StandAloneComponentData..ctor(SnapInRegistrationInfo info, Int32 bookkeepingId)
at Microsoft.ManagementConsole.Advanced.FrameworkSnapInFactory.Microsoft.ManagementConsole.Advanced.ISnapInFactory.CreateSnapIn(Int32 bookkeepingId, String snapInKey, Object& snapIn)
How can I fix it ? Please give me some advice, thank you very much.