Increase maximum size pst-files with Outlook 2007

Pst  default Size Information :How do I increase the maximum file size of an UNICODE pst file. The default size is 20 GB but as far as I know there must be a registry value that allows to increase the maximum up to approximately 4TB.



his tip does not apply to pst-files who are in the Outlook 97-2002 format (ANSI formatted pst-files).


Procedure for the Registry settings :

You need to go to the following location in the Registry;

• Outlook 2003
  HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\PST
• Outlook 2007
  HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\PST

• Outlook 2010
  HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\PST

Here you must create and set 2 new DWORD values (note that these values are case sensitive);

• WarnLargeFileSize
  Don’t set this higher than 4090445042 (decimal) or f3cf3cf2 (hexadecimal)
• MaxLargeFileSize
  Don’t set this higher than 4294967295 (decimal) or ffffffff (hexadecimal)

The first value is how many MB a user can write to a pst-file. The second value is how many MB the system can write to a pst-file. This difference has to be at least 5% since there is more written to a pst-file than just user data.

the maximum size of a pst-file has been set to 100GB with a warning at 95GB from the above settings.