This article introduces the PST files and describes how to repair your Outlook inbox with the utility named scanpst.exe. This article is relevant for the users of Microsoft Outlook 2000, 2003 or 2007.
ScanPst.exe is a repair utility supplied by Microsoft together with the installation of Microsoft Office. This tool is dedicated solely for fixing Microsoft Outlook PST files.

About Microsoft Outlook .PST files

PST stands for “Personal Folder File” and it is used by Microsoft Outlook for storing Outlook mailbox data. This file contains all your emails, contacts and any other mailbox data related to Microsoft Outlook.

PST File 2GB Limitation

Until Outlook 2002 (XP Version), the format of the PST file was according to the American National Standards Institute (ANSI) standard. This standard has limited the size of the mailbox file to 2GB at the maximum. Since Outlook 2003 the PST files are based on the UNICODE standard and therefore this limitation does not exist anymore. This limitation is a common reason for many Outlook users to use the ScanPst.exe.

Default .PST file name and location

Microsoft Outlook places PST files at the following default location: “C:\Documents and Settings\Your_Login_Name\Local Settings\Application Data\Microsoft\Outlook\”.
The default PST file name is Outlook.pst and tere is another file named archive.pst that is used to archive old mails.

Introducing the ScanPst tool

If you cannot open your Outlook mailbox folder and you receive an error message indicated that it might be due to a damaged Outlook PST file you should consider using the ScanPST utility.

“Outlook is attempting to repair your mailbox folders”

If and when Outlook cannot open the PST file it will try to fix it automatically.
Outlook will use the internal scanpst.exe utility but from our experience in many cases it will be able to successfully fix the PST file.

Scanpst – Inbox Repair Utility

Microsoft Office provides a repair tool for Outlook Pst files (Your mailbox storage file). This utility is named ScanPst and program is stored in your disk under the simple name ScanPst.Exe. This tool  can repair some of the common Outlook PST  errors. ScanPst.exe scans and attempts to repair a preselected .PST file; it analyzes its structure and checks problems it can fix. After the scanning it will provide information on the found errors offer you to repair them.

Where Can I Find ScanPst?

Simply it could be found in the following folder C:\Program Files\Common Files\System;

There you may find a folder named “MSMAPI” or “MAPI”. In this folder you will see another folder named with a numbers. For Example: 1044.
Your complete path should be somthing similar to:

C:\Program Files\Common Files\System\MAPI\1044\

However, there are two files with the following names: ScanPst.exe and ScanOst.exe. What you need is the second one.

If you cannot find the file by browsing folders, try using the “Windows Search”:

1. Click “Start” and open Windows start menu
2. Select “Search” and click Files and Folders
3. Type “ScanPst.exe” without the quotes
4. Click Find

When Scanpst Cannot Solve Your Outlook Problems?

* It cannot recover deleted messages.
* Sometimes it cannot find the problem that Outlook is reporting.
* Watch Out! it can sometimes loose data during recovery.

Before Using ScanPst.Exe

Be sure you make a backup to your Outlook PST file before running the repair process. A simple file copy would be good enough.

Sometimes when using Scanpst.exe in order to fix PST file you might receive an error message that says “Internal errors were found in this file. They must be repaired for this file to work correctly.”

This error might indicate that your default PST file is synchronized with the Microsoft Sharepoint Team services (Sharepoint is a collaboration and a team cooperation solution used in corporations).

The PST file of the Sharepoint users does not include the deleted items folder. Therefore the Scanpst.exe cannot find it and think that it might be due to an internal problem. You can ignore that message in case you are a sharepoint user or either run a third party Scanpst.exe utility that can provide you with the PST file content preview.