Microsoft 365 Admin - Use PowerShell to add Mailboxes to a Group Automatically

If you want to have Powershell automatically manage lists of mailboxes these scripts can help with that process. You'll still need to tweak them a bit to get them right.

Office 365 - Add to Distribution Group

Create a text file with one email address per line. Then run this. Modify the file path and the group name

#Need to use module ExchangePowerShell
Install-Module -Name ExchangePowerShell -Scope CurrentUser -Repository PSGallery -Force
Write-Host "Login to the Exchange account where your Groups are set. We'll use this to add groups."
Connect-ExchangeOnline

# You'll need to change the filename
# The file should have one email address per line


foreach($line in Get-Content C:\Users\pmend\Desktop\users.txt) {
    # https://docs.microsoft.com/en-us/powershell/module/exchange/add-distributiongroupmember?view=exchange-ps
    # -Identidy = Group we want to add the user to. Can be Name, Alias, Distinguished Name, Canonical DN, Email address or GUID
    Add-DistributionGroupMember -Identity "My Group" -Member $line
    Write-Output -InputObject $line
}

Exchange - Find contacts in Distribution Group and add to mailboxes.txt file

For Exchange this will loop thru the members of a distribution group and add them to the mailboxes.txt file.

#Need to use module ExchangePowerShell
Install-Module -Name ExchangePowerShell -Scope CurrentUser -Repository PSGallery -Force
Write-Host "Login to the Exchange account where your Groups are set. We'll use this to add groups."
Connect-ExchangeOnline


#remove the mailboxes.txt file
Remove-Item -Path C:\sigparser\mailboxes.txt

foreach($member in Get-DistributionGroupMember -Identity "SigParser Mailboxes") {
    Write-Output -InputObject $member
    $name = $member.Name    
    Add-Content C:\sigparser\mailboxes.txt "$name"
    #TODO: Grant delegated read access to mailbox.
    
}

If you have any questions, send us an email at support@sigparser.com. You can also book a demo session HERE.