eDiscovery Daily Blog

eDiscovery Best Practices: Repairing a Corrupted Outlook PST File


We like to believe that there will never be any problems with the data that we preserve, collect and process for eDiscovery purposes.  Sometimes, however, critical data may be difficult or impossible to use.  Perhaps key files are password protected from being opened and the only way to open them is to “crack” the password.  Or, perhaps a key file may be corrupted.  If that file is an Outlook Personal Storage Table (PST) file, that file corruption could literally make tens of thousands of documents unavailable for discovery unless the file can be repaired.

I recently had a case where 40% of the collection was contained in 2 corrupt Outlook PST files.  Had we not been able to repair those files, we would have been unable to access nearly half of the collection that needed to be reviewed for responsiveness in the case.

Fortunately, there is a repair tool for Outlook designed to repair corrupted PST files.  It’s called SCANPST.EXE.  It’s an official repair tool that is included in Office 2010 (as well as Office 2007 before it).  As a very useful utility, you might think that SCANPST would be located in the Microsoft Office 2010 Tools folder within the Microsoft Office folder in Program files.  But, you’d be wrong.  Instead, you’ll have to open Windows Explorer and navigate to the C:Program FilesMicrosoft OfficeOffice14 folder (for Office 2010, at least) to find the SCANPST.EXE utility.

Double-click this file to open Microsoft Outlook Inbox Repair Tool.  The utility will prompt for the path and name of the PST file (with a Browse button to browse to the corrupted PST file).  There is also an Options button to enable you to log activity to a new log file, append to an existing log file or choose not to write to a log file.  Before you start, you’ll need to close Outlook and all mail-enabled applications. 

Once ready, press the Start button and the application will begin checking for errors. When the process is complete, it should indicate that it found errors on the corrupted PST file, along with a count of folders and items found in the file.  The utility will also provide a check box to make a backup of the scanned file before repairing.  ALWAYS make a backup – you never know what might happen during the repair process.  Click the Repair button when ready and the utility will hopefully repair the corrupted PST file.

If SCANPST.EXE fails to repair the file, then there are some third party utilities available that may succeed where SCANPST failed.  If all else fails, you can hire a data recovery expert, but that can get very expensive.  Hopefully, you don’t have to resort to that.

By repairing the PST file, you are technically changing the file, so if the PST file is discoverable, it will probably be necessary to disclose the corruption to opposing counsel and the intent to attempt to repair the file to avoid potential spoliation claims.

So, what do you think?  Have you encountered corrupted PST files in discovery?  Please share any comments you might have or if you’d like to know more about a particular topic.

Disclaimer: The views represented herein are exclusively the views of the author, and do not necessarily represent the views held by CloudNine Discovery. eDiscoveryDaily is made available by CloudNine Discovery solely for educational purposes to provide general information about general eDiscovery principles and not to provide specific legal advice applicable to any particular circumstance. eDiscoveryDaily should not be used as a substitute for competent legal advice from a lawyer you have retained and who has agreed to represent you.