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Important This article contains information about how to modify the registry. Make sure to back up the registry before you modify it. Make sure that you know how to restore the registry if a problem occurs. For more information about how to back up, restore, and modify the registry, click the following article number to view the article in the Microsoft Knowledge Base:
256986 Description of the Microsoft Windows registry
When you try to add lots of Personal Folders files (.pst) to your e-mail profile in Microsoft Office Outlook 2003, some of the .pst files may not be added. Additionally, you receive the following error message when you try to add these .pst files to your e-mail profile programmatically:
Outlook failed to add the personal store to the session.
Alternatively, you receive the following error message when you try to add these .pst files to your e-mail profile by using the Create or Open Outlook Data File dialog box in Outlook 2003:
Out of memory or system resources. Close some windows or programs and try again.
This problem occurs because Outlook 2003 allocates more memory for caching .pst files than earlier versions of Microsoft Outlook. After you enable this hotfix, Outlook 2003 allocates the same amount of memory as earlier versions of Outlook for caching .pst files.
This problem was first fixed in a hotfix that is now contained in a service pack. If you installed the latest Office 2003 service pack, you do not have to install the hotfix.
Service pack information
This problem is corrected in Office 2003 Service Pack 3. To resolve this problem, obtain the latest service pack for Office 2003. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
870924 How to obtain the latest service pack for Office 2003
After you install the service pack, follow the steps that are listed in the "How to enable the hotfix" section of the article to set the
registry key and to activate the hotfix.
How to obtain the hotfix
This issue is fixed in the Outlook 2003 post-Service Pack 2 Hotfix Package that is dated December 6, 2005. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
899340 Description of the Outlook 2003 post-Service Pack 2 hotfix package: December 6, 2005
How to enable the hotfix
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
Quit Outlook 2003.
Click Start, click Run, type regedit in the Open box, and then click OK.
Locate and then click the following registry subkey: