Home > CiraHub Support > How to Two-Way Sync Contacts Between a GAL and an Microsoft 365 Mailbox

The GAL is a centralized address book containing the names, addresses, and email addresses of all the employees. With CiraHub, users can two-way synchronize all of their contacts in their Global Address List with multiple Microsoft 365 User Mailboxes. The need to sync the Global Address List, and the contact information it contains, is almost universal. Organizations of every size require consistent and accurate contact information.

For effective communication management in your company, the global address list and outlook contacts must be synchronized. This article will outline how to two-way contact sync a Global Address List (GAL) to an Microsoft 365 Mailbox.

Set Up a Two-Way Contact Sync Between a GAL and an Microsoft 365 Mailbox

  1. First, Log in to CiraHub. You will be taken to the onboarding wizard. (See figure below.) Next, select the object you want to sync. “Prior to setting up the Hub and Spokes in CiraHub, you will need to set up an Microsoft 365 account with the Global Admin role added to it, for setting up and granting the access permissions requested by Microsoft”. Log in to CiraHub
  2. Next start the Hub and Spoke setup. Click on “Microsoft 365 in my tenant”, then select Global Address List as the source type for your contact spoke. “Users will need to have an Microsoft 365 account with the following Exchange Online roles granted via PowerShell: Address Lists, Mail Recipient Creation, and Mail Recipients permissions which will act as a “service account” to run the GAL sync. This account does not need to have an Microsoft 365 license, and this is required for each tenant added to the Hub.”
    Select Global Address List
  3. There are two authentication methods – Credentials and Certificate based:

3.1.1 Select Credentials and Sign in with your Microsoft Admin Account’s Login and Password Information for the Global Address List Connection.“Select” Credentials and Re-Enter your Microsoft Account

3.1.2 Next the Microsoft sign-in page will appear. Provide the Email and Password to your account.Sign in with Microsoft

3.1.3 Click Accept to give CiraHub access to your Microsoft Account. You should always leave the “Consent on behalf of your organization” box unchecked when you sign in for the first time. This option lets other users under the same domain access this Hub if they login with their company email address. This user would not have access to this specific Hub, but the user would be able to login and create their own hub.Give CiraHub Permission to Microsoft

3.1.4 Select Credentials and Re-Enter your Microsoft Account Login and Password Information for the GAL Connection.Validate GAL

3.1.5 Wait for CiraHub to validate the connection to the Global Address List after entering the Microsoft Login and Password.Select Authentication Method

3.2.1 With the Certificate Authentication method, you will be prompted to either “Automatically Generate a Certificate” or you can choose to Import a PFX Certificate File and enter your password.Certificate Authentication

3.2.2 In order to two-way sync GAL contacts the user will need to enter in their Microsoft Global Admin email address. CiraHub will then store the users’ account information in the Microsoft Azure Vault when it is synced from Powershell. Enter Microsoft 365 Email

3.2.3 Lastly the user will need to wait for CiraHub to Install Certificate Based Authentication for the GAL connection and then click Next.Install Certificate

4. Type in a Spoke Name and click Next.

Add Gal spoke name

5. Next type in the Hub Name and click Create.

Add Gal Hub Name

6. Click +Add Spoke at the top-right corner of the CiraHub dashboard.


7. Select “User Mailbox” as the source type of your contact spoke.

GAL Select User Mailbox 

8. Select which User Mailbox to Sync.Gal Select User mailbox to Sync

9. Type in a Spoke Name and Click Create in order to two-way sync mailbox contacts.

Gal Mailbox Spoke Name

10. Click the Spoke that was just created. Click Turn On under the Synced tile.Sync Now

11. The Spoke Sync Options will open. (See figure below.) Click the Allow Hub to create and sync items in this spoke checkbox to two-way contact sync a Global Address List (GAL) to a User Mailbox. GAL Allow Hub to Sync

12. Users can customize sync settings by expanding the Advanced Tab and adding sync filters to the Spoke. This would enable a user to synchronize and create Hub items based on specific criteria. GAL Advanced Settings

13. Click on the GAL Tab to set up GAL Read Option Settings.Gal Settings

14. Here you can choose which Global Address List Objects (Mailboxes, Contacts, and Groups) you would like to populate this Hub with. Toggle GAL Settings

15. Click on the Hub and then click Sync Now to two-way sync the GAL to a Microsoft 365 Mailbox. GAL Sync Now

Learn More About CiraHub!

CiraHub is a two-way sync platform for shared contacts and calendars for Microsoft 365, Exchange Server, and other Microsoft Enterprise Applications users. The software is designed to make it easy for people lacking IT expertise to set up shared contact and calendar sync for their company. Click here to learn more about how you can start a CiraHub trial today!