Try these steps
* Click "File," then "Exit" to close Microsoft Outlook.
* Open Windows Explorer. Browse through your file system to where Microsoft Outlook is installed. On a 32-bit Windows system, this will be "c:\Program Files\Microsoft Office\Office XX," where "XX" is the Office version number. On a 64-bit Windows system, this will be "c:\Program Files (x68)\Microsoft Office\Office XX."
* Double-click "scanpst.exe." Click the "Browse" button and navigate to "c:\users\username\AppData\Local\Microsoft\Outlook." Double-click "archive.pst."
* Click "Start." The utility scans your archived PST file and reports any errors or corruption in the file.
* Click "Make Backup of Scanned File Before Repairing" if the Scanpst program finds errors. Click "Repair." Close the confirmation window when the repair is finished.
Or use Outlook Fix Toolbox http://www.outlook.fixtoolbox.com/
See more http://www.filerepairforum.com/forum/microsoft/microsoft-aa/outlook/669-how-to-repair-corrupted-pst