OL2000: New Outlook 2000 Feature Removes Deleted Data from .pst and .ost Files

A feature has been added to ensure that deleted data is removed from .pst and .ost files. This feature is activated through a registry entry. When it is enabled, deleted data is overwritten when Outlook is shut down. Most data is removed and overwritten during normal operation, but a small percentage can remain if this feature is not activated.

A supported feature that modifies the default behavior of the product is available from Microsoft. However, this feature is intended to modify only the behavior that this article describes. Apply this feature only to systems that specifically require it.

If the feature is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the feature.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific feature. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the feature is available. If you do not see your language, it is because the feature is not available for that language.

The English version of this feature should have the following file attributes or later:
This feature was first made available in Microsoft Office 2000 SR-1.

To apply this feature, obtain Microsoft Office 2000 Service Release 1 (SR-1). To obtain SR-1, click the article number below to view the article in the Microsoft Knowledge Base: The Oqfefe3886.msp file is a Microsoft Installer Patch file. To apply the patch, right-click the file, and then click Apply Patch. For an Administrative installation, please see the following article in the Microsoft Knowledge Base: On each system where you want this behavior, you must add a registry entry.

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
On computers running Microsoft Windows 95 or Microsoft Windows 98:

1. Click Start, click Run, and then type regedit in the Open box.
2. In Registry Editor, locate or create the following key:
   HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Outlook\PST
3. If you see the PSTNullFreeOnClose entry (the PSTNullFreeOnClose entry is of type DWORD) under the PST key, go on to step 8. If the PSTNullFreeOnClose entry is not under the PST key, you must add it. To add the PSTNullFreeOnClose key with its associated DWORD value, follow steps a through d:
   1. Click the PST key.
   2. On the Edit menu, point to New, and then click DWORD Value. You see a new DWORD with the temporary name of New Value #1 appear under the PST key.
   3. Click New Value #1, and then on the Edit menu, click Rename.
   4. Change the name to PSTNullFreeOnClose.
4. Double-click PSTNullFreeOnClose to open it.
5. Under Base, click Decimal.
6. In the Value data box, set the PSTNullFreeOnClose value to one of the following:
   0 - original behavior, do not delete data on close
   1 - remove deleted data from PST and OST files on close
   After you type the setting that you want in Value data, click OK.
7. Quit Registry Editor.

On computers running Microsoft Windows NT or Microsoft Windows 2000:

1. Click Start, click Run, and then type regedt32 in the Open box.
2. In Registry Editor, locate or create the following key:
   HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Outlook\PST
3. If you see the PSTNullFreeOnClose entry (the PSTNullFreeOnClose entry is of type DWORD) under the PST key, double-click it, and then go to step 8. If the PSTNullFreeOnClose entry is not under the PST key, you must add it. To add the PSTNullFreeOnClose key with its associated DWORD value, follow steps a through d:
   1. Click the PST key.
   2. On the Edit menu, click Add Value.
   3. In the Value Name box, type PSTNullFreeOnClose.
   4. In the Data Type list, click REG_DWORD, and then click OK.
4. In the Value data box, set the PSTNullFreeOnClose value to one of the following:
   0 - original behavior, do not delete data on close
   1 - remove deleted data from PST and OST files on close
   After you type the setting that you want in Value data, click OK.
5. Under Radix, click Decimal. Click OK.
6. Quit Registry Editor.