This article documents the method for clearing the Windows paging file (Pagefile.sys) during the shutdown process, so that no unsecured data is contained in the paging file when the shutdown process is complete.

Some third-party programs may temporarily store unencrypted (plain-text) passwords or other sensitive information in memory. Because of Windows virtual memory architecture, this information may be present in the paging file.

Although clearing the paging file is not a suitable substitute for physical security of a computer, you may want to increase the security of data on a computer while Windows is not running.

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

1.	Start Registry Editor.
2.	Change the data value of the ClearPageFileAtShutdown value in the following registry key to a value of 1: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\ Memory Management If the value does not exist, add the following value: Value Name: ClearPageFileAtShutdown Value Type: REG_DWORD Value: 1
3.	Restart your computer for the change to take effect.

Note: When you enable this registry change, your computer may take more time to shut down. For additional information about Session Manager memory management settings, click the article number below to view the article in the Microsoft Knowledge Base: