Troubleshooting MDT (read your log files)

I was on the TechNet MDT forums the other day and I read somebody claiming that the MDT logfiles were too verbose and too hard to read. This is only kind of true. They certainly are verbose (which is in fact a good thing). These logs will contain lots of information, and while it can seem overwhelming at first, they’re only hard to read when you’re not using CMTrace. This is a free tool you can download from Microsoft. It’s part of the SCCMTooklit downloads available here:


When installing the SCCM2012R2 Toolkit, just select client tools.

Pass on the ServerTools and Select Client Tools

Once that’s installed you may need to set CMTrace as your default viewer for logfiles. That’s easy. Open CMTrace once and it’ll ask to be the default. The hard part is knowing which log files to check.

CMTrace should ask you this right away – Select yes

Yes, sometimes knowing if half the battle, and with MDT that battle is knowing where to look for log files. If the imaging hasn’t started and you’re still in WinPE, look in X:\MININT\SMSOSD\OSDLOGS. If the task sequence has started and that PC has at least imaged, look in C:\MININT\SMSOSD\OSDLOGS. If the task sequence has finished, or at least been wrapped up cleanly, look in %WINDIR%\TEMP\DeploymentLogs. MDT will move everything there at the end.

The core MDT log file is BDD.log. MDT will dump that to the Windows temp folder on the system being imaged. If you don’t have server logging set up in your share, set that up. It’ll save you time down the road. It will let you dump logs back to MDT at the end of the deployment. There’s lots of logs for each script that runs as part of the task sequence and you can even specify to log MSI installs during the deployment as well.

The first place to look when troubleshooting MDT is the BDD.log file in the windows temp.
This is your logfile in notepad. Not pretty. I’d even say this is practically useless
CMTrace allows you easily read MDT log files, it highlights warnings, errors and points out problems for you.

Other log files you may want to look for:

  • ZTIApplications.log – When troubleshooting application installs
  • ZTIDrivers.log – When troubleshooting MDT Driver injection
  • ZTIDomainJoin.log – When troubleshooting joining the domain

Finally, there’s a great guide here that reminds us the most important thing about troubleshooting MDT:

“When you know which log files to research for what failure condition and at what time, issues that were once mysterious and difficult to understand may become clear and understandable.”

For more info on Advanced MDT troubleshooting, check out Keith Garner’s guide on TechNet here: