Exchange 2013 CU 6 update fails on transport service

i ran the update and it keeps getting the following error and i cannot find any info on the error

Exchange Server component Mailbox role: Transport service failed.
Error: Error:
The following error was generated when "$error.Clear();
          $feVdirName = "PowerShell (Default Web Site)";
          $beVdirName = "PowerShell (Exchange Back End)";
          $vdirName = "PowerShell";
          $InternalPowerShellUrl="http://" + $RoleFqdnOrName + "/powershell";

          get-PowerShellVirtualDirectory -ShowMailboxVirtualDirectories -server $RoleFqdnOrName -DomainController $RoleDomainController | where { $_.Name -eq $beVdirName -or $_.Name -eq $feVdirName } | remove-PowerShellVirtualDirectory -DomainController $RoleDomainController;

          new-PowerShellVirtualDirectory $vdirName -Role Mailbox -DomainController $RoleDomainController -BasicAuthentication:$false -WindowsAuthentication:$true -RequireSSL:$true -WebSiteName "Exchange Back End" -Path ($RoleInstallPath + "ClientAccess\PowerShell-Proxy");
          new-PowerShellVirtualDirectory $vdirName -Role Mailbox -InternalUrl $InternalPowerShellUrl -DomainController $RoleDomainController -BasicAuthentication:$false -WindowsAuthentication:$false -RequireSSL:$false -WebSiteName "Default Web Site" -AppPoolId "MSExchangePowerShellFrontEndAppPool";
        " was run: "System.ArgumentException: The virtual directory 'PowerShell' already exists under 'MST-MAIL1.fibigroup.net/Exchange Back End'.
Parameter name: VirtualDirectoryName
   at Microsoft.Exchange.Configuration.Tasks.Task.WriteError(Exception exception, ErrorCategory category, Object target, Boolean reThrow, String helpUrl)
   at Microsoft.Exchange.Configuration.Tasks.Task.WriteError(Exception exception, ErrorCategory category, Object target)
   at Microsoft.Exchange.Management.SystemConfigurationTasks.NewExchangeVirtualDirectory`1.InternalValidate()
   at Microsoft.Exchange.Configuration.Tasks.Task.<ProcessRecord>b__b()
   at Microsoft.Exchange.Configuration.Tasks.Task.InvokeRetryableFunc(String funcName, Action func, Boolean terminatePipelineIfFailed)".