How to Create Global Contacts in an Office 365 Tenant

Exchange Public Folders or Mail Contacts

A recent post to the Office 365 Technical Discussions Facebook group came from a small Office 365 tenant (a voluntary fire brigade with 47 members) who wanted to share global contacts such as the town mayor or local companies. The only solution they had discovered was to create a public folder to hold contacts. This will work, but it’s an Outlook-only solution because Outlook is the only email client that understands how to use the shared contacts from a public folder as an address list (see below)

Mail Contacts Have Best Client Support

Given the widespread use of mobile devices and the undesirability of setting up and managing public folders in a small Office 365 tenant, mail contacts seem like a better approach. A mail contact is an object created in Exchange for someone outside your organization. Each contact has an email address and other properties that you’d expect to find in an address book, such as first and last name, display name, mailing address, and phone numbers. The email address used for a mail contact must be unique. In other words, it cannot be assigned to another mail-enabled object already known to your organization (including guest user accounts).

Mail contacts are included in the Exchange Global Address List (GAL) and Offline Address Book (OAB), so they are available to all the Microsoft email clients – Outlook desktop (Windows and Mac), OWA, and Outlook for iOS and Android. Because mail contacts exist in the Exchange directory, they are also available to third-party email clients, if those clients choose to include the necessary support (here’s one example that does).

The Downside of Mail Contacts

The downside of mail contacts is that these objects can only be added by an Exchange administrator (or more precisely, an account that has been assigned the Mail Recipients RBAC role). Once your account has the necessary permissions, it can add or update mail contacts using the Office 365 Admin Center (Users – Contacts), the Recipients section of the Exchange Admin Center (EAC), or by running the New-MailContact PowerShell cmdlet.

Use PowerShell to Import Contacts from a CSV File

One way to approach the problem is to ask someone who doesn’t have administrative permission to maintain a CSV file holding details of the common contacts. You can add as many of the properties supported by Exchange for mail contacts as you wish. Once the file is ready, PowerShell can process its contents.

This very simple PowerShell code reads the CSV file shown above and creates a new mail contact for each line found in the file. Note that the New-MailContact cmdlet creates a new mail contact and the Set-Contact cmdlet updates some of the extended properties, like phone numbers.

$InputContacts = import-csv c:\temp\inputcontacts.csv
Write-Host $InputContacts.Count "contacts found"
ForEach ($Contact in $InputContacts) {
    $Alias = $Contact.First + "." + $Contact.Last
    # Real simple code to make sure that we have an alias
    If ($Alias -eq $Null) { $Alias = $N.Name.Split("")[0] + "." + $N.Name.Split("")[1] }
    If ((Get-Recipient -Identity $Contact.EmailAddress -ErrorAction SilentlyContinue) -eq $Null) {
       # Recipient is not known, so we can add them
       Write-Host "Adding contact" $Contact.EmailAddress
       New-MailContact -Name $Contact.Name -ExternalEmailAddress $Contact.EmailAddress -Alias $Alias -FirstName $Contact.First -LastName $Contact.Last
       # Update country and phone numbers
       Set-Contact -Identity $Alias -MobilePhone $Contact.MobilePhone -Phone $Contact.WorkPhone -CountryOrRegion $Contact.Country -Company $Contact.Company }
}

Free Book about Eradicating Public Folders

If your organization is considering moving from public folders, consider reading the eBook “The Complete Guide to Eradicating Legacy Public Folders” to get some ideas for how you might approach the task.

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For more information about public folders, see Chapter 8 of the companion volume for the Office 365 for IT Pros eBook. Mail contacts are covered in Chapter 7 of the main book. You get both the main and companion volumes when you subscribe to Office 365 for IT Pros.