365-command-logoThis week I want to talk about Office 365 Calendar Invites and Meeting Requests Coming Across as Plain-text Email to Non-Mailbox Users within the GAL

Office 365

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A default setting within Office 365 that can lead to some frustration is that External Contacts and Mail-Enabled Users (not to be confused with Mailbox-enabled) will often will not receive calendar/meeting invites properly in that they arrive in the recipients’ mailboxes as simple plain-text emails that they cannot accept or decline and thus not get placed into their calendars.

Basically, Office 365 uses MAPI Rich Text formatting as the default for these users/contacts, thus transforming HTML messages such as calendar invites into plain-text.

What you need to do is turn off this setting for all Mail-Enabled users and External Contacts that are listed in your GAL.

Mail-Enabled Users

To do this, for all Mail-Enabled users, execute the following:

Get-MailUser -Resultsize Unlimited | Set-MailUser -UseMapiRichTextFormat Never

To do this, for one particular mail-enabled user, perform the following command:

Set-MailUser “Alias of User” –UseMapiRichTextFormat Never

For example, for user information, perform the following:  Set-MailUser “information” –UseMapiRichTextFormat Never

IF you need to back out of this or “undo” for any reason, instead of stating “Never” at the end of the cmdlet, input “UseDefaultSettings” instead.

External Contacts

For External Contacts, the Nomenclature is similar, instead you replace “MailUser” with “MailContact” within the cmdlet.

Get-MailContact -Resultsize Unlimited | Set-MailContact -UseMapiRichTextFormat Never

To do this, for one particular mail-enabled user, perform the following command:

Set-MailContact “Alias of User” –UseMapiRichTextFormat Never

For example, for user Dottie Pepper, you need to perform the following:  Set-MailContact “Dottie Pepper” –UseMapiRichTextFormat Never

NOTE:  To get a list of all of either the MailUsers or External Contacts within your Office 365 GAL, input the following cmdlets:

  Get-MailUser | More     or            Get-MailContact | More

And that is Justin’s Tech Tip of the week on how to set up Office 365 Calendar Invites and Meeting Requests so they don’t come across as plain-text email to non-mailbox users within the GAL.

To see topics covered by previous Tech Tips of the Week, see below:

Shared Mailboxes Part I -What to do if you want or need to convert a full (user) Office 365 mailbox into a Shared Mailbox.

Shared Mailboxes Part II – How do you create a shared mailbox from scratch and then add permissions to them?  

Mailbox Archiving