How to: Add Multiple Email Addresses to Mail Contacts in Microsoft 365

Introduction

Microsoft 365 administrators often need to add multiple email addresses to mail contacts. While the Microsoft 365 admin center provides a user-friendly interface for managing contacts, it has limitations when it comes to adding multiple email addresses to a single contact. This article explains the challenges administrators face and provides clear, up-to-date solutions for adding multiple email addresses to mail contacts in Microsoft 365.

Problem Statement

The Microsoft 365 admin center is designed for simplicity, which sometimes comes at the cost of advanced functionality. When using the Office 365 admin panel, you can only add a single email address to a mail contact. This limitation becomes problematic in scenarios where:

• You need external contacts to receive emails sent to multiple addresses
• You're managing contacts who use different email addresses for different purposes
• You need to set up forwarding to multiple destinations
• You're migrating from systems where contacts had multiple email addresses

The admin interface doesn't provide any built-in method to add secondary email addresses to mail contacts, requiring administrators to seek alternative approaches.

Solution Options

Option 1: Using PowerShell to Add Multiple Email Addresses

PowerShell remains the most effective method for adding multiple email addresses to mail contacts in Microsoft 365. Here's how to do it:

Step 1: Connect to Exchange Online PowerShell

Modern Microsoft 365 environments require modern authentication methods. The latest recommended approach is to use the Exchange Online V3 PowerShell module:

1. Install the Exchange Online PowerShell module if you haven't already:

   Install-Module -Name ExchangeOnlineManagement -Force -AllowClobber
   

2. Connect to Exchange Online with modern authentication:

   Connect-ExchangeOnline -UserPrincipalName your_admin@yourdomain.com
   

This modern connection method works with multi-factor authentication and is more secure than older connection methods.

Step 2: Add Multiple Email Addresses to a Mail Contact

Once connected, you can add multiple email addresses to contacts using the Set-MailContact cmdlet:

Set-MailContact "Contact Name" -EmailAddresses "SMTP:primary.email@domain.com","smtp:secondary.email@domain.com"

Important notes about this command:

• The primary address should have uppercase "SMTP:" prefix
• Secondary addresses must use lowercase "smtp:" prefix
• Having multiple uppercase entries can cause mail flow problems
• You can add as many secondary addresses as needed by adding more comma-separated values

Step 3: Verify the Configuration

To confirm that your changes have been applied successfully:

Get-MailContact "Contact Name" | Select-Object -ExpandProperty EmailAddresses

This command will display all email addresses associated with the contact, allowing you to verify that both the primary and secondary addresses have been correctly added.

Option 2: Bulk Operations with PowerShell

For scenarios requiring adding multiple email addresses to many contacts at once, you can use PowerShell with a CSV file:

1. Create a CSV file with columns for contact name and email addresses
2. Import the CSV and process each contact:

# PowerShell
$contacts = Import-Csv -Path "C:\Contacts.csv"
foreach ($contact in $contacts) {
    Set-MailContact $contact.Name -EmailAddresses $contact.EmailAddresses.Split(",")
}

Option 3: Microsoft 365 Admin Center (Limited Functionality)

While the admin center cannot add multiple email addresses to contacts directly, you can use it to:

1. Navigate to the Microsoft 365 admin center
2. Go to Users > Contacts
3. Add individual contacts with their primary email address
4. Use PowerShell separately to add secondary addresses

Confirmation

To confirm this has worked run the following command:

1. Get-MailContact "User Name" | select -ExpandProperty EmailAddresses
2. Check the admin web interface and check the external email address is correct. This is the address receiving all incoming email for the contact.

Conclusion

While Microsoft 365's admin interface doesn't provide native capabilities for adding multiple email addresses to mail contacts, PowerShell offers a powerful solution to overcome this limitation. Using the Exchange Online PowerShell module with modern authentication ensures you can manage mail contacts efficiently while maintaining security compliance. The key points to remember are:

• The primary email address requires the uppercase "SMTP:" prefix
• Secondary addresses must use the lowercase "smtp:" prefix
• Always verify your changes after implementation
• is required for this functionality; there's no web interface alternative

For organizations managing large numbers of contacts with multiple email addresses, investing time in learning commands will significantly improve administrative efficiency.

Ready to enhance your Microsoft 365 contact management? Here are your next steps:

1. Install the tools: Ensure you have the latest Exchange Online PowerShell V3 module installed on your administrative workstation
2. Document your contacts: Create a spreadsheet of contacts requiring multiple email addresses
3. Test in a controlled environment: Practice the PowerShell commands on a test contact before implementing widely
4. Implement and verify: Apply your changes and verify functionality by sending test emails
5. Create a process: Document your procedure for future reference and team knowledge sharing

Need more assistance with Microsoft 365 administration? Consider engaging with our Microsoft 365 consultants who can provide tailored guidance for your organization's specific needs. Contact us today.

References

• How to update contact information in Exchange Online in Office 365
• Bulk import external contacts to Exchange Online