Step 1: Exit Outlook and all mail-enabled applications.
Locate the Inbox Repair Tool (Scanpst.exe)
Open the Start menu, type C:\Program Files\Microsoft Office\Office12\SCANPST.EXE in the search or Run dialog, and press Enter.
Alternatively, you can find this file by clicking My Computer and browsing to the destination; once there, double-click SCANPST to open it.