How to Create Office 365 Mailboxes in Hybrid Configuration?

A common issue faced by businesses and enterprises moving their on-premises Exchange mailboxes to the cloud is the confusion that arises while creating new mailboxes. While this task might appear simple at first, there can be several issues even after setting up Exchange hybrid configuration with Exchange Online (EXO) and proceeding with mailbox migrations. For example, if admins create new mailboxes on Exchange Online (EXO) instead of their on-premises Exchange Server, they will not be able to manage the Exchange attributes because there is no mail-enabled user in the on-premises Exchange Server. In this article, we will explore how to create Office 365 mailboxes in a hybrid configuration.

What Are the Different Methods for Creating Office 365/ Microsoft 365 Mailboxes?

Admins can create Office 365/ Microsoft 365 mailboxes in an Exchange hybrid configuration either using the Exchange Admin Center or PowerShell.

Office 365/ Microsoft 365 Hybrid Mailboxes Using Exchange Admin Center

Creating users from the Exchange Admin Center is the simplest method for creating Microsoft 365/ Office 365 mailboxes. Admins can create hybrid Office 365 mailboxes using Exchange Admin Center by following the steps below.

• Navigate to Recipients > Mailboxes. Expand the “+” sign above the “Display Name” column, and select the Microsoft 365 mailbox in the Exchange Admin Center of the on-premises hybrid server.
• Enter the details in the Dialog Box and edit user mailbox properties as necessary. With this method, there is no need to set up an Active Directory account manually, as Exchange creates the AD object automatically.
• On saving the details, AD Connect will synchronize data and the user details will appear in Microsoft 365 with an Exchange Online mailbox. An appropriate license will have to be assigned after the synchronization.
• Licenses can be assigned from the Microsoft 365 portal in the Product Licenses field.

Office 365/ Microsoft 365 Hybrid Mailboxes Using PowerShell

Exchange PowerShell cmdlet can be used to automatically provision an Office 365/ Microsoft 365 mailbox for an existing Active Directory (AD) user. It can also be used to add Exchange Online mailboxes in the Exchange Admin Center of the on-premises Exchange Server. The RemoteMailbox cmdlet can be used to create on-premises mail users with special attributes to indicate that the associated mailbox should be created when the directory is synchronized. Policies, such as Unified Messaging or compliance policies, that apply to recipients in the on-premises Exchange organization, can be applied to recipients in the service later.

Apps4Rent Can Help with Office 365/ Microsoft 365 Hybrid Configuration

Although it is possible to create Microsoft 365/Office 365 accounts in Active Directory and use AD Connect to synchronize user data with the Microsoft 365 accounts, the Exchange attributes might not reflect accurately on the local Exchange Admin Center. This might result in incorrect data and conflicting information after syncing the on-premises Exchange Server with Exchange Online.

As a Microsoft Gold Partner in specializations such as Cloud Platform, Cloud Productivity, Collaboration, and Content, Apps4Rent can help businesses migrate to Microsoft 365/ Office 365 and assist with the hybrid setup. Contact our Microsoft certified advisors, available 24/7 via phone, chat, and email for assistance.