How to configure the size limit for both .pst and .ost files in Outlook 2007 and in Outlook 2003

Microsoft Office Outlook 2007 and Microsoft Office Outlook 2003 supports both American National Standards Institute (ANSI) and UNICODE personal folders (.pst) and offline folder (.ost) files. You can use the following four registry entries to limit the size of both the .pst and the .ost files: • The MaxFileSize registry entry • The WarnFileSize registry entry • The MaxLargeFileSize registry entry • The WarnLargeFileSize registry entry Note The WarnLargeFileSize and WarnFileSize registry entries do not enable Outlook to warn you before the file size limit is reached. The default values for these entries are: MaxLargeFileSize = 20 GB WarnLargeFileSize = 19 GB MaxFileSize = 1.933 GB WarnFileSize = 1.816 GB The policy location for the registry entries is located in the following path in Registry Editor.

Outlook 2007

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Outlook\PST

The user preference location for the registry entries is located in the following path in Registry Editor:

HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\PST

Outlook 2003

HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\11.0\Outlook\PST

The user preference location for the registry entries is located in the following path in Registry Editor:

HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\PST

Check out Microsoft's KB article 832925 for more details on this topic.