Where is scanpst.exe and how to find it

PST and OST corruption – the root of most Outlook issues

A corrupted PST or OST file is one of the most common causes of problems with Outlook. If an Outlook mail file is corrupted, Outlook does not necessarily tell you about it. However, Outlook will start failing in random and unpredictable ways. From something relatively minor, like messages not turning read after you open them, to crashes, freezes and inability to launch Outlook. A large portion of our support requests have nothing to do with TechHit products, but are resolved by running scanpst to fix errors in the PST / OST file.

How to find scanpst on your computer

Outlook Open File LocationIf you have Microsoft Office installed, you have scanpst.exe installed as well. It is located in the same folder as Outlook. Here is an easy way to find it:


  1. Open the Task Manager.
  2. Find Outlook on the Processes tab.
  3. Right-click on Outlook and select “Open File Location”. The screenshot on the right shows Windows 8. In Windows 7, “Open File Location” is the first command on the right-click menu.
  4. You will see Windows Explorer open the folder in which Outlook is installed. Scanpst is located in the same folder.




IMPORTANT: you have to run scanpst repeatedly on every PST/OST file, until it tells you that there are no more errors in the file. You will find additional instructions in the first part of this article.

Microsoft knowledge base article about scanpst.


After you have fixed your email files, check out TechHit add-ins for Microsoft Outlook which will help you keep Outlook running in tip-top shape and save you an hour of time each and every week.




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We are getting ready to release a brand new product. It is designed for Outlook users who use their Inbox as a ToDo list, which is most of us.

If you believe you could use a new way of managing ToDo items in your Inbox and are willing to provide Beta feedback, you can sign up to be a beta tester. The number of spots for the first phase is limited. If you are interested, please sign up today.

We are very excited about the way the product is shaping, are looking forward to sharing it with you and hearing your feedback!


And, of course, we already have a solution for messages which you keep for future reference and on which no additional actions are necessary. You can use SimplyFile to file email messages to the right Outlook folder with one click or SimplyTag to tag and categorize email messages.


How to prevent Outlook from adding line breaks to sent plain text messages

When you send a plain text message, by default, Outlook will wrap text and insert line breaks at 76 characters. This might break your formatted paragraphs and URL links.

There is a solution which requires registry changes, however there also an option that fixes it without touching the registry. Here are the steps:

  1. Click on the File tab and select Options.
  2. Click on “Advanced” in the left column of the Options window.
  3. Scroll down to the “International Options” section.
  4. Change “Preferred encoding for outgoing messages” to “Unicode (UTF-8)”.
  5. Click “OK” at the bottom of the Options window.
  6. Restart Outlook

That should do it.

Note: This only works for Outlook 2010 or newer. For older versions of Outlook (2007 and 2003), you have to use the registry tweak. Google outlook “WrapLines”.

This solution was discussed in this thread.


Do you have too many messages in your Inbox? Try SimplyFile  – Intelligent filing assistant for Microsoft Outlook.



Outlook crashing, hanging and freezing – common causes and solutions

This article describes some of the most common reasons that cause Outlook to become unstable, crash, hang or freeze.

If you are experiencing issues with your Outlook, try these items one-by-one and hopefully one of them will help.

Corrupted PST file

By far the most common reason for Outlook crashes, instability and unexplained weird behavior is a corrupted PST or OST file.

If you have an Exchange (or Office 365) account, you have an OST file. Follow the next section – “Corrupted OST file”. For other account types, follow this section.

Microsoft is aware of this issue and provides a tool to fix it – Inbox Repair tool (scanpst). Follow the steps listed in that Microsoft Knowledge Base article to run ScanPST. Run it on all your PST files.

Important: In many cases, ScanPST requires more than one pass to fix a corruption. Run ScanPST repeatedly, until it reports that there are no more errors.

In some cases, a corruption might be so bad that ScanPST is unable to fix it. ScanPST will tell you that there are no more errors, but you would still experience issues. In this case, you should create a new PST file and copy all items from the old PST into the new one. After you do that, close the old PST file (Right-click the top-most folder of the PST, then select “Close”) and start using the new one.

Note: You can also use scanPST to check and fix your OST files.

Corrupted OST file

To fix an OST file for an Exchange-based account, you simply rename it and let Outlook rebuild it from the server.

Before deleting the OST, check that Outlook is fully synced. (It should say “All folders up to date” in the status bar at the bottom of the main Outlook window).

First, find your OST file:

  • Click “File” in the upper-left corner of the main Outlook window.
  • Click the square “Account Settings” button, then the “Account Settings” menu command.
  • Switch to the “Data files” tab.
  • Select the OST file.
  • Click “Open File Location”. This will open File Explore and select the OST file.

Then rename the OST file, so Outlook rebuilds it.

  • Close Outlook.
  • Rename the OST file. For example “Mary.ost” to “DELETEME_Mary.ost”. (You can delete the old file later).
  • Restart Outlook and let it rebuild the OST file. Note: This operation might take a long time if you have a large Exchange mailbox, but you can still use Outlook while it happens.

For a non-Exchange account OST, such as IMAP, use the ScanPST method in the first section of this article.

Corrupted Profile

Sometimes an Outlook profile might get corrupted. In this case, you have to create a new profile.

Corrupted Outlook Configuration Files

[This section is no longer relevant. It applied to old versions of Outlook.]

In addition to PST, OST and profiles, Outlook has several other files which might get corrupted. If the above steps did not help, please try renaming outcmd.dat, extend.dat and Frmcache.dat as described in Part 2 of this article.

Misbehaving Add-ins

Running unnecessary add-ins may make Outlook slower and even cause stability issues. Check what add-ins you have installed. You probably have more add-ins installed than you think. Use the following instructions to see what add-ins you have installed and disable the ones you are not using. Leave only the Add-ins you absolutely must have in Outlook.

How to disable addins in Outlook 2016, 2013 and 2010
How to disable addins in Outlook 2007
How to disable addins in Outlook 2003

Keep Windows Up To Date

Regularly use Windows Update to keep your computer up to date with the latest patches and service packs. We recommend that you configure Windows to check for updates automatically.

Hope you found this article useful. If you have additional tips, please share them in comments below.

TechHit products will help you spend less time managing email and keep Outlook running in tip-top shape.

Outlook 2007 slow folder switching, missing AutoArchive – KB2412171

Microsoft has identified several issues with a recent Outlook updated (KB2412171).

If you are experiencing one of the following issues, you might be affected:

  • Slow performance while switching between Outlook folders.
  • Missing AutoArchive functionality.
  • Issues with password authentication while sending or receiving email.

Microsoft recommends uninstalling update KB2412171 if you experience any of the above symptoms. Only Outlook 2007 is affected. You can find more details in this article. Microsoft also published  KB2485531 on this issue.

Update: On January 11 2011, Microsoft issued an update which is supposed to fix the three issues listed above.

Outlook Addin or toolbar disappears when you close or restart – how to fix

Some of you may experience a situation where an add-in goes missing or a toolbar disappears when you close and reopen Outlook. This is usually caused by one of several reasons.

1. Outlook does not fully exit when you close it

In this case, Outlook does not exit completely when you close its main window. This is usually caused by a third party add-in which prevents Outlook from exiting. You can usually recover the missing toolbar by following these steps:

  • Close Outlook
  • Open the Task Manager
  • Switch to the Processes tab
  • Find OUTLOOK.EXE in the “Image Name” column
  • Select it and click “End Task”
  • Wait 5 seconds, then start Outlook again.

That should bring your missing toolbar back.

If this keeps happening to you, you might want to disable some of the add-ins you have installed, to find which one is causing this issue.

How to disable add-ins in Outlook 2010
How to disable add-ins in Outlook 2007
How to disable add-ins in Outlook 2003

2. Outlook disabled the add-in

If the above steps did not help, please try rebooting. If you still do not see the toolbar, it is possible that Outlook disabled the add-in. In that case, you can re-enable it using the following steps:

Outlook 2010:

  • Select the “File” ribbon tab
  • Click “Options”
  • Click “Add-Ins” in the left column of the Options window
  • Select “Disabled Items” in the “Manage” drop-down and click “Go”
  • Select the add-in from the list and click “Enable”
  • Restart Outlook

Outlook 2007:

  • Click on “Help->Disabled Items” menu command
  • Select the add-in from the list and click “Enable”
  • Restart Outlook

Outlook 2003:

  • Click on “Help->About Microsoft Outlook” menu command
  • Click the “Disabled Items” button in the lower right-hand corner
  • Select the add-in from the list and click “Enable”
  • Restart Outlook

What new features would you like to see in OutTwit

OutTwit LogoMany of you have sent us messages saying how much you enjoy using OutTwit. Thank you for your kind words! We always like to hear from happy users.

What would make OutTwit even more useful to you? What new features would you like to see added in the future?

  • Multiple account support?
  • Spell checker?
  • TwitPic integration?
  • What else?

Let us know in the comments below. Thanks, and keep on OutTwitting!