How To Increase maximum size for pst-files and ost-files Outlook
Via the Registry
To increase the maximum size of pst-files and ost-files in Outlook, you’ll need to create and set 2 values in the following location in the registry:
- Outlook 2003
- Outlook 2007
- Outlook 2010
- Outlook 2013
- Outlook 2016
The following 2 new DWORD values must be created or set;
Don’t set this higher than 4090445042 (decimal) or f3cf3cf2 (hexadecimal)
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 or ost-file before receiving a warning that the file is full. The second value is how many MB the system can write to a pst-file or ost-file.
In this example the maximum size of pst-files and ost-files has been set to 100GB with a warning at 95GB.
Note: Although the Registry path says “PST”, it also applies to ost-files.