1. Open the repair utility provided with Outlook. Because there is no shortcut from Outlook or your computer desktop, you may not be aware it exists. To launch the program from Vista or Windows 7, navigate to C:\Program Files (x86)\Microsoft Office\Office12. Look for the Scanpst.exe file. Double click on the file to launch the utility.
2. The program presents a dialogue box that allows you to browse to your PST file. Unless you designated a different location for your PST file, the best way to find the file is to do a search by entering "%appdata%\Microsoft\Outlook" into your search window from either the start menu or address bar.
3. After locating your PST file, click on the "Start" button to begin the scanning function of the program. This scan may take some time depending on the size of your PST file. When the scan is finished, the utility will report if errors were found or not. If so, you have the option of backing up your PST file before the repairs are executed. Click on the check box and select a target path where you want the backup PST file to be saved.
4. Click on the "Repair" button. Again, be patient as the program executes repair actions. When finished, the "Repair complete" dialogue box appears. The Scanpst.exe program will log actions performed in the repair process to a log file located in the same folder as your original PST file. The file will be a simple text (TXT) document with the same name as your PST file.
5. With the repair procedure complete, re-open Outlook
6. In case you can't do anything even via the guide, make use of powerful instrument
PST Open File Tool