Sample Powershell to identify groups with HBI classification and have external users
Here's some sample PowerShell that will - Identify Office 365 Groups with a "HBI" classification and if there are Guest users within the group. - Identify the owners of the respective groups - Identify the specific guest users within each group This could be used in conjunction with Microsoft Flow to programmatically - automate the removal of guest users from groups with specific classifications - automate an email to the owners of the group to alert the presence of external (guest) users in an Office 365 Group - automate an email to the owners of the group to indicate the Office 365 Group is not compliant with guest access policy and then programmatically disable/remove external guests $Groups = Get-UnifiedGroup -Filter {GroupExternalMemberCount -gt 0} | Where-Object {$_.Classification -eq 'HBI'} $groups| Format-Table -AutoSize DisplayName, Classification, GroupMemberCount, GroupExternalMemberCount, Managedby ForEach ($G in $Groups) { $Ext = Get-UnifiedGroupLinks -Identity $G.Identity -LinkType Members ForEach ($E in $Ext) { If ($E.Name -match "#EXT#") { Write-Host "Group " $G.DisplayName "includes guest user" $E.Name } } }