Policy
Upgrade only the default store
This policy setting allows you to specify that only the default data file is upgraded on the first boot of Outlook. If you enable this policy setting, only the data file associated with your delivery mailbox is upgraded. If you disable or do not configure this policy setting, all Outlook Data Files are upgraded.
PackMicrosoft Office
CategoryMicrosoft Outlook 2016 / Miscellaneous / PST Settings
Policy ID
5882171f5b18Internal name
L_UpgradeOnlyTheDefaultStoreRegistry
Copy registry mappings
HKCU\software\policies\microsoft\office\16.0\outlook\setup\upgradedefaultonly (enabled) = 1
HKCU\software\policies\microsoft\office\16.0\outlook\setup\upgradedefaultonly (disabled) = 0Policy notes
This policy setting allows you to specify that only the default data file is upgraded on the first boot of Outlook. If you enable this policy setting, only the data file associated with your delivery mailbox is upgraded. If you disable or do not configure this policy setting, all Outlook Data Files are upgraded.
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