Tag Archives: Windows Backup

Windows Server Backup stuck on “Running Consistency Check for Application Exchange” for Exchange 2010

If you use Windows Backup to back up your Exchange 2010 databases, you may find yourself in a situation where the backup appears hung at “Running consistency check for application Exchange” for hours and hours. You should also see Event ID 3156 in the Application log on the server.

The most likely cause of this is that there are an excessive amount of log files present (like thousands and thousands), which can happen with a large amount of activity or if you haven’t performed a successful backup in a while.

This can really pose a problem if you find yourself rapidly running out of hard disk space, and are concerned the backup will not complete and flush the logs before you do run out.

There are two easy fixes. The first (and safest) thing to do is to simply let it complete. However, depending on the number of log files that can take a really long time… hours and even days.

The second is a little more drastic, but desperate times call for desperate measures. First, stop the active backup. Then, simply go to the properties of each database, and enable Circular Logging. With Exchange 2010 SP1, you do not need to dismount the mailbox store and then mount it again for this to take effect. It should take less than an hour, but ultimately you will see the log files evaporate into the ether. Once that happens, you can disable circular logging and then run your backup again. This time, you should see it pass by the “Running consistency check for application Exchange” step much more quickly.

If that doesn’t resolve it, you might have a problem with the VSS writers. If you run the following command from an elevated command prompt you can check that all of them are in “Stable” state.

vssadmin list writers

If it looks like you have a problem, you can increase your logging level by using the following command in the Exchange Management Shell.

Set-EventLogLevel "MSExchangeIS\9002 System\Exchange Writer" -Level Expert

For good measure, I would also suggest restarting the Microsoft Exchange Server Extension for Windows Server Backup service.

The enhanced logging should point you in the right direction if there are deeper issues. If you do have deeper issues, I would suggest a full server reboot first. before taking any further troubleshooting steps. If you have a chronic issue that keeps coming back though, I would highly recommend troubleshooting it to resolution rather than just rebooting every time.

When finished, don’t forget to return it to the default logging level:

Set-EventLogLevel "MSExchangeIS\9002 System\Exchange Writer" -Level Lowest

Hope this helps!