How to Sync Contacts of Two or More Office 365 or Exchange Mailboxes?

    The problem

    You have two separate Outlook, Microsoft 365 or Exchange mailboxes, and you would like to have a (customizable) two-way sync of contacts between them? Or maybe you want to push contacts from one common shared contact list, GAL, or a public folder to all tenant users? Whatever the use case, you're in the right place!

    In this article, we'll show you how to sync betweem two contact lists using the SyncPenguin platform. If you are interested in more complex syncing scenarios, please feel free to contact us.

    The sync allows a variety of connection combinations and scenarios, including between different Exchange domains or Office 365 tenants. You can sync records between pairs of accounts, from one shared account to all, or arrange any other custom sync behavior.

    Note that apart from Office 365 the service can sync with multiple Exchange EWS-based services, including:

    • Microsoft Office 365
    • Exchange On-Premise Server
    • Exchange Online
    • Outlook on the Web
    • Amazon WorkMail
    14-day free trial • no credit card • full support

    1. Sign up

    The first step is to sign up and log in to the SyncPenguin Dashboard. That's the place where you create, monitor, and manage your synchronizations.

    2. Create contacts sync

    The next step is to create the sync. To do this, go to the Synchronizations section of the dashboard and click the plus 'New sync' button. You'll see a wizard page, where you need to follow three steps of sync creation:

    • Select the first app to sync (Exchange or Office 365 Contacts in our case).
    • Select the other app (also Exchange or Office 365 Contacts).
    • Click Create.

    3. Sign in to Office 365 or Exchange accounts

    Great! You are almost there. The next step is to allow SyncPenguin access to both of your O365 accounts in the Access & Settings sections that you'll see on the sync page. To do that, expand the corresponding access panel, click the 'Connect' button and authenticate your Office 365 account through OAuth.

    In case you want to sync to Exchange on-premise server, you cannot sign in like that. Instead, you should enter the server Endpoint URL, Username (which should just be your email in most cases), and Password fields directly manually. You can always contact us if you're not sure how to connect!

    Below we provide more details on how to connect both Office 365 and Exchange accounts.

    How to connect Office 365?

    The Office 365 Contacts account connection section will look like this:

    Account for Office 365 Contacts
    Office 365 Contacts
    User group
    Additional settings
    User group
    Additional settings

    How to connect Exchange On-Premises?

    The Exchange On-Premises Contacts account connection section will look like this:

    Account for Exchange On-Premises Contacts
    Exchange On-Premises Contacts
    Additional settings
    Additional settings

    4. Start the sync

    That's it! Well, almost. The last thing, of course, is to start the sync.

    In order to do that just click the 'Start sync' button. You'll be prompted with a couple of options of what to do with contacts you currently have in your lists. The options are the following:

    1. Only sync new data, meaning contacts that will be added or updated starting from now.
    2. Merge all historic data two-way: merge contacts from both lists. If you have contacts copied in both lists, they should be merged instead of creating a duplicate.
    3. Merge A → B: one-way merge of all contacts from the first connected list to the second.
    4. Merge B → A: similar to the previous option but in the opposite direction.
    Start sync
    We'll be checking every 10 minutes for changes in your data.
    What should we do initially with already existing contacts?

    After the initial merge is done, the sync will be automatically triggered from time to time (you can configure the interval) to check for updates.


    So there you have it. That how simple it is. If you have any questions, visit our website or feel free to contact us directly. And remember: with our platform, it always possible to customize the sync so that it fits your needs!