Failed to put Exchange into maintenance mode & CU6 won't install? "Unable to set monitoring and server state to inactive"

I have Exchange 2013 installed on the only domain controller.

When I go to put Exchange 2013 into maintenance mode from the Exchange Management Shell using the command:

Set-ServerComponentState server.domain.local -Component ServerWideOffline -State Inactive -Requester Maintenance

I get the following error:

"Set-ServerComponentState : The term 'Set-ServerComponentState' is not recognized as the name of a cmdlet, function,
script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is
correct and try again.
At line:1 char:1
+ Set-ServerComponentState server.domain.local -Component ServerWideOffline -State ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : ObjectNotFound: (Set-ServerComponentState:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException"

How do I put this Exchange server into maintenance mode?

I am trying to put Exchange into maintenance mode as the CU6 Cumulative Update is failing with the below error:

Error:The following error was generated when"$error.Clear();
          try
          {
            $Target = $env:COMPUTERNAME
            try
            {
              $exSrv = get-ExchangeServer $Target -ErrorAction SilentlyContinue
            }
            catch
            {
              Write-ExchangeSetupLog -Warning "Unable to set monitoring and server state to inactive.Setup will continue.";
            }

            if ($exSrv -eq $null)
            {
              Write-ExchangeSetupLog -Warning "$Target isnot an ExchangeServer.Unable to set monitoring and server state to inactive.Setup will continue.";
              return
            }

            Set-ServerComponentState $Target -Component Monitoring -Requester Functional -State Inactive
            Write-ExchangeSetupLog -Info "Monitoring has been set to Inactivewhile setup is running."

            Set-ServerComponentState $Target -Component RecoveryActionsEnabled -Requester Functional -State Inactive
            Write-ExchangeSetupLog -Info "RecoveryActionsEnabled has been set to Inactivewhile setup is running."

            Set-ServerComponentState $Target -Component ServerWideOffline -Requester Functional -State InActive
            Write-ExchangeSetupLog -Info "The server state has been set to Inactivewhile setup is running."
          }
          catch
          {
            Write-ExchangeSetupLog -Warning "Unable to set monitoring and server state to inactive.Setup can notcontinue.";
            throw;
          }" was run:"Microsoft.Exchange.Data.Directory.ADOperationException: Active Directory operation failed on EXCH01.domain.local. This error is not retriable. Additional information: Insufficient access rights to perform the operation.
Active directory response: 00002098: SecErr: DSID-03150E49, problem 4003 (INSUFF_ACCESS_RIGHTS), data 0
 ---> System.DirectoryServices.Protocols.DirectoryOperationException: The user has insufficient access rights.
   at System.DirectoryServices.Protocols.LdapConnection.ConstructResponse(Int32 messageId, LdapOperation operation, ResultAll resultType, TimeSpan requestTimeOut, Boolean exceptionOnTimeOut)
   at System.DirectoryServices.Protocols.LdapConnection.SendRequest(DirectoryRequest request, TimeSpan requestTimeout)
   at Microsoft.Exchange.Data.Directory.PooledLdapConnection.SendRequest(DirectoryRequest request, LdapOperation ldapOperation, Nullable`1 clientSideSearchTimeout, IActivityScope activityScope, String callerInfo)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException, Boolean isSync)
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.Data.Directory.ADDataSession.AnalyzeDirectoryError(PooledLdapConnection connection, DirectoryRequest request, DirectoryException de, Int32 totalRetries, Int32 retriesOnServer)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException, Boolean isSync)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException)
   at Microsoft.Exchange.Data.Directory.ADDataSession.Save(ADObject instanceToSave, IEnumerable`1 properties, Boolean bypassValidation)
   at Microsoft.Exchange.Management.SystemConfigurationTasks.SetServerComponentState.InternalProcessRecord()
   at Microsoft.Exchange.Configuration.Tasks.Task.<ProcessRecord>b__b()
   at Microsoft.Exchange.Configuration.Tasks.Task.InvokeRetryableFunc(String funcName, Action func, Boolean terminatePipelineIfFailed)".Error:The following error was generated when"$error.Clear();
          try
          {
            $Target = $env:COMPUTERNAME
            try
            {
              $exSrv = get-ExchangeServer $Target -ErrorAction SilentlyContinue
            }
            catch
            {
              Write-ExchangeSetupLog -Warning "Unable to set monitoring and server state to inactive.Setup will continue.";
            }

            if ($exSrv -eq $null)
            {
              Write-ExchangeSetupLog -Warning "$Target isnot an ExchangeServer.Unable to set monitoring and server state to inactive.Setup will continue.";
              return
            }

            Set-ServerComponentState $Target -Component Monitoring -Requester Functional -State Inactive
            Write-ExchangeSetupLog -Info "Monitoring has been set to Inactivewhile setup is running."

            Set-ServerComponentState $Target -Component RecoveryActionsEnabled -Requester Functional -State Inactive
            Write-ExchangeSetupLog -Info "RecoveryActionsEnabled has been set to Inactivewhile setup is running."

            Set-ServerComponentState $Target -Component ServerWideOffline -Requester Functional -State InActive
            Write-ExchangeSetupLog -Info "The server state has been set to Inactivewhile setup is running."
          }
          catch
          {
            Write-ExchangeSetupLog -Warning "Unable to set monitoring and server state to inactive.Setup can notcontinue.";
            throw;
          }" was run:"Microsoft.Exchange.Data.Directory.ADOperationException: Active Directory operation failed on EXCH01.domain.local. This error is not retriable. Additional information: Insufficient access rights to perform the operation.
Active directory response: 00002098: SecErr: DSID-03150E49, problem 4003 (INSUFF_ACCESS_RIGHTS), data 0
 ---> System.DirectoryServices.Protocols.DirectoryOperationException: The user has insufficient access rights.
   at System.DirectoryServices.Protocols.LdapConnection.ConstructResponse(Int32 messageId, LdapOperation operation, ResultAll resultType, TimeSpan requestTimeOut, Boolean exceptionOnTimeOut)
   at System.DirectoryServices.Protocols.LdapConnection.SendRequest(DirectoryRequest request, TimeSpan requestTimeout)
   at Microsoft.Exchange.Data.Directory.PooledLdapConnection.SendRequest(DirectoryRequest request, LdapOperation ldapOperation, Nullable`1 clientSideSearchTimeout, IActivityScope activityScope, String callerInfo)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException, Boolean isSync)
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.Data.Directory.ADDataSession.AnalyzeDirectoryError(PooledLdapConnection connection, DirectoryRequest request, DirectoryException de, Int32 totalRetries, Int32 retriesOnServer)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException, Boolean isSync)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException)
   at Microsoft.Exchange.Data.Directory.ADDataSession.Save(ADObject instanceToSave, IEnumerable`1 properties, Boolean bypassValidation)
   at Microsoft.Exchange.Management.SystemConfigurationTasks.SetServerComponentState.InternalProcessRecord()
   at Microsoft.Exchange.Configuration.Tasks.Task.<ProcessRecord>b__b()
   at Microsoft.Exchange.Configuration.Tasks.Task.InvokeRetryableFunc(String funcName, Action func, Boolean terminatePipelineIfFailed)".Error:The following error was generated when"$error.Clear();
          try
          {
            $Target = $env:COMPUTERNAME
            try
            {
              $exSrv = get-ExchangeServer $Target -ErrorAction SilentlyContinue
            }
            catch
            {
              Write-ExchangeSetupLog -Warning "Unable to set monitoring and server state to inactive.Setup will continue.";
            }

            if ($exSrv -eq $null)
            {
              Write-ExchangeSetupLog -Warning "$Target isnot an ExchangeServer.Unable to set monitoring and server state to inactive.Setup will continue.";
              return
            }

            Set-ServerComponentState $Target -Component Monitoring -Requester Functional -State Inactive
            Write-ExchangeSetupLog -Info "Monitoring has been set to Inactivewhile setup is running."

            Set-ServerComponentState $Target -Component RecoveryActionsEnabled -Requester Functional -State Inactive
            Write-ExchangeSetupLog -Info "RecoveryActionsEnabled has been set to Inactivewhile setup is running."

            Set-ServerComponentState $Target -Component ServerWideOffline -Requester Functional -State InActive
            Write-ExchangeSetupLog -Info "The server state has been set to Inactivewhile setup is running."
          }
          catch
          {
            Write-ExchangeSetupLog -Warning "Unable to set monitoring and server state to inactive.Setup can notcontinue.";
            throw;
          }" was run:"Microsoft.Exchange.Data.Directory.ADOperationException: Active Directory operation failed on EXCH01.domain.local. This error is not retriable. Additional information: Insufficient access rights to perform the operation.
Active directory response: 00002098: SecErr: DSID-03150E49, problem 4003 (INSUFF_ACCESS_RIGHTS), data 0
 ---> System.DirectoryServices.Protocols.DirectoryOperationException: The user has insufficient access rights.
   at System.DirectoryServices.Protocols.LdapConnection.ConstructResponse(Int32 messageId, LdapOperation operation, ResultAll resultType, TimeSpan requestTimeOut, Boolean exceptionOnTimeOut)
   at System.DirectoryServices.Protocols.LdapConnection.SendRequest(DirectoryRequest request, TimeSpan requestTimeout)
   at Microsoft.Exchange.Data.Directory.PooledLdapConnection.SendRequest(DirectoryRequest request, LdapOperation ldapOperation, Nullable`1 clientSideSearchTimeout, IActivityScope activityScope, String callerInfo)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException, Boolean isSync)
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.Data.Directory.ADDataSession.AnalyzeDirectoryError(PooledLdapConnection connection, DirectoryRequest request, DirectoryException de, Int32 totalRetries, Int32 retriesOnServer)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException, Boolean isSync)
   at Microsoft.Exchange.Data.Directory.ADDataSession.ExecuteModificationRequest(ADObject entry, DirectoryRequest request, ADObjectId originalId, Boolean emptyObjectSessionOnException)
   at Microsoft.Exchange.Data.Directory.ADDataSession.Save(ADObject instanceToSave, IEnumerable`1 properties, Boolean bypassValidation)
   at Microsoft.Exchange.Management.SystemConfigurationTasks.SetServerComponentState.InternalProcessRecord()
   at Microsoft.Exchange.Configuration.Tasks.Task.<ProcessRecord>b__b()
   at Microsoft.Exchange.Configuration.Tasks.Task.InvokeRetryableFunc(String funcName, Action func, Boolean terminatePipelineIfFailed)"."