Posts tagged Outlook

Find the Microsoft Outlook temporary OLK folder

Where does Microsoft create the Outlook Temporary folder (better known as the OLK folder)??? Or, where does Microsoft store temporary data such as attachments? Where the heck is that PESKY OLK folder??




Depending on the operating system, version of Outlook AND user logged in, the OLK temporary folder will be created in a different spot. To find where it’s been created, open the Windows registry using regedit32.exe and use the MAP below:

Outlook 97 HKEY_CURRENT_USER\Software\Microsoft\Office\8.0\Outlook\Security
Outlook 98 HKEY_CURRENT_USER\Software\Microsoft\Office\8.5\Outlook\Security
Outlook 2000 HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Outlook\Security
Outlook 2002/XP HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Outlook\Security
Outlook 2003 HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Security
Outlook 2007 HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Security


When you open file attachments that are considered safe, Outlook places these attachments in a subdirectory under the your Temporary Internet Files directory as an extra precaution. When Outlook first tries to use a temporary file, it examines the registry to determine whether or not the TEMP OLK folder has already been created. If yes, it uses the folder. If no, it creates a random folder then stores the path in the registry location mentioned above.

For example:

Let’s say your running Windows XP and Outlook 2003. When you open your first attachment your computer will create the following sub-folder to temporary store the attachment:

C:\Documents and Settings\username\Local Settings\Temporary Internet Files\OLKxxx

In this example, username is the user name that is used by the person who is currently logged on to the is a randomly generated sequence of letters and numbers.

This information can be very useful and potentially dangerous. For instance, let’s say you open an attachment, make a bunch of changes then forget to save it…. Chance are, you can probably find the OLK folder and recover the document (if you have autosave on).

Now the bad news, let’s say you open an attachment which contains sensitive or confidential information. While reading the document, Outlook unexpectedly closes. In this scenario, the attachment will remain in the Outlook Temporary folder indefinitely because Outlook cannot remove the temporary file while it’s open. Now let’s say your PC is stolen…… Yup, all your documents are just sitting there for anyone to open. Believe me? Just go look. If you’ve been using your computer for any length of time I bet you will find 1-2 dozen files sitting there for anyone to open and read.

At work, I use Outlook ALL DAY. When I upgraded my PC to Microsoft Vista and Office 2007, I immediately began looking for the EVER important OUTLOOK TEMPORARY FOLDER in order to 1: Encrypt it using EFS and 2: Find a document which I wrote and somehow lost. MISSION ACCOMPLISHED! I found the document AND encrypted it without an issue.

Clear the Outlook Email Address Auto Complete Cache

Background: Outlook 2003 and Outlook 2007 has a feature called Email Address Auto Complete. As you type in an email address into the TO: or CC: field (and BCC: field I imagine) outlook will display a list of matching email addresses from the outlook auto-complete cache.

As convenient as the Auto Complete feature is, there are times when you need to remove these cached email addresses from the cache. Perhaps you just sent an email and you found out you made a typo….. Unfortunately that typo will remain in you cache until you delete it.

Solution: The fix is easy:

  1. Type the email address you wish to clear from the cache until outlook displays it as shown above.
  2. Press the down arrow key to select the email address and press the delete button.
  3. All Done

Solution #2 : Another option if you want to delete all addresses in the cache file (outlook.nk2):

  1. Close Outlook
  2. Open Windows Explorer or IE and Paste%APPDATA%\Microsoft\Outlook into the address bar.
  3. Delete the file Outlook.nk2 file in this folder
  4. All Done

Solution #2 is comparable to the the “Nuclear Bomb” being that it will delete ALL your cached email addresses.  It should only be used if you want to wipe the file clean or if you have corruption issues with your .nk2 file.  Once you delete the .nk2 file, the next time you open Outlook it will automatically create a new .nk2 cache file and Outlook will once again begin caching the email addresses you use.