Prevent PST Usage Growth PowerShell

Hello,

If you’re planning an Office 365/ Exchange Online migration, you may want to prevent PST usage and growth before their importation in a later migration phase. To do this, you can create a GPO with the Office ADMX files.

You can download the Office ADMX files from Microsoft:

• Office 2010: https://www.microsoft.com/en-us/download/details.aspx?id=18968
• Office 2013: https://www.microsoft.com/en-us/download/details.aspx?id=35554
• Office 2016: https://www.microsoft.com/en-us/download/details.aspx?id=49030

Here-under an example of the GPO settings:

Prevent PST Usage Growth PowerShell – GPO

You can also flip some registry keys, depending on the Office version installed:

$OutlookVersion = '16'
#PSTDisableGrow
New-ItemProperty -Path "HKCU:\Software\Microsoft\Office\$OutlookVersion.0\Outlook\PST" -PropertyType DWORD -Name PSTDisableGrow -Value 1
#DisablePST
New-ItemProperty -Path "HKCU:\Software\Microsoft\Office\$OutlookVersion.0\Outlook\PST" -PropertyType DWORD -Name DisablePST -Value 1

Outlook version:

• Outlook 2003 : 11
• Outlook 2007 : 12
• Outlook 2010 : 14
• Outlook 2013 : 15
• Outlook 2016 : 16

You need to adapt $OutlookVersion to your Office deployment.