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Microsoft Tightens Outlook Groups Security in Policy Switch

Microsoft is changing its default security settings for Outlook and SharePoint Online groups to make them private by default, instead of public.

Only approved group members are able to view Outlook groups that are set to private. In an announcement Tuesday, Microsoft said the policy switch to private by default will only affect new deployments and "will not affect the settings of existing sites."

The new policy was also announced in the Office 365 Message Center on April 19.

The switch will occur over the coming months, "starting with Outlook on the Web," the browser-based version of Outlook. It'll also happen at some point for Outlook apps on PC and Mac, Outlook Mobile, plus the Outlook 2016 desktop client.  

The change will occur for SharePoint Online team sites connected with groups at the end of this month for organizations getting "targeted release" updates (that is, test releases). It'll get finalized and released to all Office 365 subscribers "over the following months," Microsoft's announcement indicated.

Organizations wanting to use the original "public" by default setting can restore it using an Exchange Online PowerShell cmdlet, as described in this support article. The support article notably includes a table that shows that default privacy settings already are in effect for Office 365 groups used with SharePoint, Stream and Microsoft Teams applications.

Microsoft apparently made this change to private by default in reaction to user feedback. As noted by Tony Redmond, a Microsoft Most Valuable Professional (MVP) and Exchange expert, the request to make Office 365 groups private by default is the third highest request listed at Microsoft's Office 365 Groups user voice forum page.

Last year, Microsoft announced an Office 365 private groups setting would be imposed for Outlook users, but only for manager groups. Back then, MVPs had complained that this policy could clutter up global address lists, and that it would be much better to have it as an optional setting. Now, Microsoft has adopted the private by default setting for all Outlook groups users.

About the Author

Kurt Mackie is senior news producer for 1105 Media's Converge360 group.

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