Today I was installing CU6 and I got this message. Can I roll-back or How to fix? 

<processrecord>Error:
The following error was generated when "$error.Clear();
            # Apply XML Transforms to FIPS configuration file if schema changed
            Write-ExchangeSetupLog -Info "Applying XML Transforms to FIPS configuration";

            $FipsBinPath = [System.IO.Path]::Combine($RoleInstallPath, "FIP-FS\bin");
            [Reflection.Assembly]::LoadFile([System.IO.Path]::Combine($FipsBinPath, "FSCConfigurationServerInterfaces.dll"));
            [Reflection.Assembly]::LoadFile([System.IO.Path]::Combine($FipsBinPath, "FSCConfigSupport.dll"));

            $configServer = New-Object Microsoft.FSC.Configuration.ConfigManagerClass;
            if(! $configServer)
            {
              Write-ExchangeSetupLog -Error "Configuration Server object could not be created.";
            }
            else
            {
              try
              {
                $configServer.Upgrade();
                Write-ExchangeSetupLog -Info "Configuration.xml was upgraded successfully";
              }
              catch
              {
                Write-ExchangeSetupLog -Error "Upgrade of Configuration.xml was unsuccessfull, $_";
              }
              # Stop the process if it is still running
              # We silently continue because if process has already exited, Stop-Process will throw error
              # Error is non-terminating and so can be suppressed
              Stop-Process -processname FSCConfigurationServer -Force -ErrorAction SilentlyContinue;
            }
          " was run: "System.Exception: Upgrade of Configuration.xml was unsuccessfull, Exception calling "Upgrade" with "0" argument(s): "Could not find file 'C:\Program Files\Microsoft\Exchange Server\V15\FIP-FS\Data\ConfigurationServer.lkg'."
   at Microsoft.Exchange.Configuration.Tasks.Task.ThrowError(Exception exception, ErrorCategory errorCategory, Object target, String helpUrl)
   at Microsoft.Exchange.Configuration.Tasks.Task.WriteError(Exception exception, ErrorCategory category, Object target)
   at Microsoft.Exchange.Management.Deployment.WriteExchangeSetupLog.InternalProcessRecord()
   at Microsoft.Exchange.Configuration.Tasks.Task.<ProcessRecord>b__b()
   at Microsoft.Exchange.Configuration.Tasks.Task.InvokeRetryableFunc(String funcName, Action func, Boolean terminatePipelineIfFailed)".
</processrecord>

Try this and see if it helps....

1. Go to C:\Program Files\Microsoft\Exchange Server\V15\FIP-FS\Data
2. Deleted the file "Configuration.xml" and renamed "Configuration.xml.back" to Configuration.xml.
3. Then try to re-install Exchange Mailbox Server.

Reference: https://social.technet.microsoft.com/Forums/office/en-US/b2f53158-3a75-4224-8826-1d92ef7b5922/exchange-2013-cu7-installation-crash-on-mailbox-role-transport-service?forum=exchangesvrdeploy

Perhaps you can go for newer CU as well instead of CU6. CU9 is the latest one...

HI Amit,

I already did without lucky. I've delete configuration.xml and renamed configuration.xml.bak , run again Cu6 and receive the same error, also i  have tried  copy those files from another server with just mailbox rule and updated to there but doesn't work too. at this moment I moving mailboxes to another server for next Monday everybody works normal and I will try to update directly to CU9.

I already knew about cu9 but I thought I needed to install all Cumulative updates one by one until the last version, i didn't know I could update from from cu5 to cu9 directly.

Hi,

How about the things upgrade to CU9? Is this upgrade sucessful?

Please come back to us.

Best Regards.

no, doesn't work,If I just click on setup telling last setup was incompleted and give me back a error, when I try to run setup.exe /m:recoverserver at the end I receive the same error too,

• Edited by srjohny 20 hours 35 minutes ago e