exchange 2013 CU23

Hey all,

Im stuck in exchange server 2013 CU 23 installation step 10 of 14

I have server 2008 r2

Error:
The following error was generated when "$error.Clear();
          if (!$RoleIsDatacenter -and !$RoleIsDatacenterDedicated)
          {
          $mailboxId = [Microsoft.Exchange.Management.Migration.MigrationBatchIdParameter]::MigrationMailboxName;
          $dispName = "Microsoft Exchange Migration";
          $mbxs = @(Get-Mailbox -Arbitration -DomainController $RoleDomainController -Filter {Name -eq $mailboxId});
          $migrationMailbox = $null;

          if ($mbxs.Length -eq 0)
          {
          Write-ExchangeSetupLog -Info ("Retrieving mailbox databases on Server=$RoleFqdnOrName.");
          $dbs = @(Get-MailboxDatabase -Server:$RoleFqdnOrName -DomainController $RoleDomainController);
          if ($dbs.Length -ne 0)
          {
          Write-ExchangeSetupLog -Info ("Retrieving users with Name=$mailboxId.");
          $arbUsers = @(Get-User -Filter {Name -eq $mailboxId} -IgnoreDefaultScope -ResultSize 1);
          if ($arbUsers.Length -ne 0)
          {
          Write-ExchangeSetupLog -Info ("Enabling mailbox $mailboxId.");
          $migrationMailbox = Enable-Mailbox -Arbitration -Identity $arbUsers[0] -DisplayName $dispName -database $dbs[0].Identity;
          }
          }

Please help