Introduction #
By default, Microsoft allows additional storage providers to be added in the Outlook Web App (OWA). In doing so, users are able to add personal storage services such as Box, Dropbox, Facebook, Google Drive, OneDrive Personal, etc to save and attach files.
Blocking additional storage providers in Outlook Web App is important because it can help prevent users from using non-approved cloud storage services to store email attachments. This can help ensure that all email attachments are stored in a secure, centrally-managed location, and that they are properly backed up and protected from data loss.
Additionally, blocking additional storage providers can help prevent users from sharing sensitive information with unauthorized parties, and can reduce the risk of data leaks and compliance violations. By blocking access to non-approved storage providers, organizations can maintain greater control over their data and ensure that it is properly protected.
User Impact #
Medium
End users who have configured additional storage providers will no longer be able to access them. End users who wish to add additional storage providers will be unable to do so.
Parameters #
Allow Additional Storage Providers – Yes/No
No is set by default and is recommended
Admin Portal Reference #
This setting cannot be configured using the admin portal.
PowerShell Reference #
Note – It is possible to have more than one OWA Mailbox Policy in a tenant. This setting will check, update and report on each policy it finds.
To allow additional storage providers in OWA
Set-OwaMailboxPolicy -Identity [policy identity] -AdditionalStorageProvidersAvailable $trueTo disallow additional storage providers in OWA
Set-OwaMailboxPolicy -Identity [policy identity] -AdditionalStorageProvidersAvailable $falseIf Action is set to Notify #
When the Allow Additional Storage Providers setting matches the yes/no value provided by the parameter the setting will report the OWA Mailbox Policy as compliant.
When the Allow Additional Storage Providers setting does not match the yes/no value provided by the parameter the setting will report the OWA Mailbox Policy as non-compliant.
If Action is set to Enforce #
When the Allow Additional Storage Providers setting matches the yes/no value provided by the parameter the setting will report the OWA Mailbox Policy as compliant.
When the Allow Additional Storage Providers setting does not match the yes/no value provided by the parameter the setting will be updated to match the parameter and report as compliant-fixed.
