OST Files Not Shown With Windows Explorer
When I browse a backup with Windows Explorer I don't see my OST files for Outlook. I see my PST files but not the OST ones, even they're on the my hard drive. Why would OST files not be showing up?
OST files are not locally stored on your PC rather, they are stored on an Exchange Server. Seperate email backup feature was discontinued in TI 2015 however, PST files which are locally stored on your PC are still backed up. See the KB Article below:
Thanks Bob, that's the reason.
OST and OAB files are not backed up. You can see why in the Windows registry. Open regedit.exe and and navigate to HKLM\System\CurrentControlSet\Control\BackupRecovery/FilesNotToSnapshot. You will see the OST and OAB files listed on the right side. You can edit/remove those keys to include the files in your backups.Microsoft has created these registry entries for some reason I don't understand and Acronis is following.
Thanks. I agree this doesn't make much sense, especially since the OSTs are local on a machine and necessary to restore Outlook to just as it was before. Does anyone have a batch script that can change those keys so I don't have to edit them manually (we have several machines)?
OST and OAB files are stored on the local machine - they are an offline version of the files stored on the Exchange Server. When Outlook is running from an Exchange profile, the local and the server files are kept synchronized. If you disconnect from the network you can still access your email store because of the local OST file. Your changes are saved in the file and it is re-synchronized the next time that you reconnect to the network.
My guess is that Microsoft chose to exclude OAB and OST files because if you do back them up and then later restore them, they are outdated if you have since connected to the Exchange server and made changes. When you do reconnect with an out-of date file, the server recognizes that the local file is out of date and has been since modified, so it may be missing some emails that were sent/received since the backup. This triggers a re-download of the entire OST file across the network to replace the outdated file. So Microsoft probably decided that it wasn't worth it to back up the OST file. My Windows Home Server 2011 OS also excludes these files from client backups. It excludes too many other files also but that's another story.
If you image your machine with the recovery version of TrueImage 2015, then the OST and OAB files are included in the backup. But you have to be careful when you restore the image if you want to avoid triggering a complete replacement of the OST file when you reconnect to the server.
Whenever I need to restore, I first close Outlook and make a copy of the OST file. After restoring the OS partition with TI, I then copy the saved OST file back to the disk to replace the outdated one in the image. This never triggers a reload of the OST file and works every time. I have to do this because I have a slow DSL connection at home and it takes hours to download a new copy of the OST file. If you're on a fast network (at work we have a GB LAN) this process takes seconds, so it isn't worth worrying about.