BT were recently censured for a mistake by their communications agent Porter Novelli where hundreds of customer email addresses were leaked by their accidental inclusion on the To: and CC: lines instead of Bcc:. To rub salt in the wound further, Porter Novelli issued a statement claiming the original message had been recalled (practically impossible with such a large audience) which both angered and insulted the intelligence of the recipients. The privacy and anonymity of all those recipients was violated by one eager mailer who forgot Bcc…
part 1 of this guide I covered how to create a DDG that sent mail to users that had “Parent” in their CustomAttribute1 field. I also described how to test the DDG to ensure that the right users had been added.
In this part I’ll cover how to restrict access to the DDG. Sending mass emails to parents is not an uncommon event, but what if you want to moderate emails before they’re allowed to be sent? What if you want the DDG to be hidden from all your users to prevent misuse?
1. Hide DDG from the GAL
We can modify our existing “All Parents” group by using the following code that will remove it from the GAL:
Set-DynamicDistributionGroup "All Parents" –HiddenFromAddressListsEnabled $true
You can re-enable visibility in the GAL by changing $true to $false.
2. Enable moderation
The following code will turn moderation on, set the DDG moderator to a user whose alias is james, and send notifications only to internal senders whose mail is rejected by the moderator.
Set-DynamicDistributionGroup "All Parents" –ModerationEnabled $true –ModeratedBy james -SendModerationNotifications Internal
Any mail that is sent to the “All Parents” DDG now has to be manually moderated before it is passed on to the recipients.
More information on the additional parameters you can use with Dynamic Distribution Groups can be found on the Outlook Live help website.
Following on from my previous post detailing the options for sending mass mails, I thought it would be useful to post the PowerShell code I’ve used in the past to create, and test, DDGs.
DDGs, rather than store a set list of recipients, will mail users who satisfy the criteria upon which the group is based. There are a variety of attributes you can use, such as CustomAttributeX (where X is a number 1 to 15). I’ve included some sample steps:
1. Create new dynamic distribution group:
New-DynamicDistributionGroup "All Parents" -IncludedRecipients MailboxUsers, MailContacts –ConditionalCustomAttribute1 Parent
This code creates a new DDG called “All Parents” (AllParents@your-domain.ac.uk) and includes your mailbox users and external contacts in the search on CustomAttribute1, which in this case looks for “Parent”.
2. Test DDG criteria:
$DDG = Get-DynamicDistributionGroup "All Parents"; Get-Recipient -RecipientPreviewFilter $DDG.RecipientFilter
This code will display all the users the DDG would mail if you were to send a message to it. You should see all users who have “Parent” in CustomAttribute1 listed.
It is important to consider setting restrictions on who can mail the DDG – by default it cannot be mailed from outside of your Outlook Live domain; however unless you specifically set it your DDG will be visible in the GAL and “mailable” by all your users.
For information on hiding and moderating your DDGs, read part 2!