You exit Microsoft Office Outlook 2010, Microsoft Office Outlook 2007, or Microsoft Office Outlook 2003 while email attachments are open. These attachments are from email messages that are in a secure Outlook folder. Alternatively, Outlook unexpectedly closes.
When this occurs, the attachments remain in the "Outlook Secure Temporary File" folder. This occurs even if you close the attachments after you exit Outlook.
Additionally, if you open the attachment to the email message from the Reading pane, you do not receive a prompt to save changes when you exit Outlook.
This problem occurs because Outlook 2010, Outlook 2007, and Outlook 2003 cannot remove the temporary file or dispose of the secure temporary folder while the attachments are open.
This problem has been resolved in Microsoft Outlook 2010 Service Pack 1 (SP1) and in the Microsoft Office Outlook 2007 hotfix package dated June 29, 2010. These updates are described in the following Microsoft Knowledge Base articles.
When you open file attachments that are considered safe, Outlook 2010, Outlook 2007, and Outlook 2003 puts these attachments in a subdirectory of the Temporary Internet Files directory as an additional precaution. When Outlook 2010, Outlook 2007, or Outlook 2003 first tries to use a temporary file, it examines the registry to determine whether the following value exists, depending on your version of Outlook.
Value Name: OutlookSecureTempFolder Data Type: REG_SZ
If the value exists, and if the value contains a valid path, Outlook 2010, Outlook 2007, or Outlook 2003 uses that location for its temporary files.
If the registry value does not exist, or if the value points to an invalid location, Outlook 2010, Outlook 2007, or Outlook 2003 creates a new subdirectory under the Temporary Internet Files directory and then puts the temporary file in the new subdirectory. The name of the new subdirectory is unknown and is randomly generated, depending on your version of Outlook. In this situation, to locate this subdirectory, depending on your version of Windows and your version of Outlook, follow these steps.
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:
322756 How to back up and restore the registry in Windows
Windows XP clients:
Click Start, and then click My Computer.
On the Tools menu, click Folder Options.
On the View tab, make the following changes:
Select the Show hidden files and folders option.
Click to clear the Hide protected operating system files (Recommended) check box.
Continue with the next set of steps based on your version of Outlook.
For Outlook 2010 and for Outlook 2007:
Click Start, click Run, type the following command (including the quotation marks), and then click OK.
"C:\Documents and Settings\ username \Local Settings\Temporary Internet Files\Content.Outlook"
Open the subfolder under the Content.Outlook folder whose folder name is a randomly generated sequence of letters and numbers. For example, FW0B6RID.
Note There may be more than one subfolder with a randomly generated name under the Content.Outlook folder.
For Outlook 2003:
Click Start, click Run, type Regedit, and then click OK.
Locate and then click the following registry subkey: