Avatar of BBrayton

asked on 

How to setup AD sync with 2019 server and office 365 with a .local internal Domain

We are going to setup Ad Sync for one of our clients and would like to know if there will be an issue with syncing users in active directory with .local domain.

And what steps should I take to get it working?
Microsoft OfficeMicrosoft 365* Azure Active Directory Domain Services

Avatar of undefined
Last Comment
Avatar of DEMAN-BARCELO (MVP) Thierry
Flag of France image


technically, the steps are easy.
- Add the suffix for  all the messaging domains that you will use to authenticate (in the Domains and Trusts console)
- Change the userprincipalname of each users to set the main email address of the user.

ADSync cannot migrate your default domain ".local" but will migrate all these users using the new UPN.

If you keep the default domain for users, this domain will not be used by O365, and will be replaced by "@YourTenant.OnMicrosoft.com".

Avatar of Saif Shaikh
Saif Shaikh
Flag of India image

Deman is right. You can install Azure AD Connect on Windows 2019 and change the users UPN from .local to .com since if you do not change and sync users from syncing OU, these users will have a primary email set as "YourTenant.OnMicrosoft.com".

No issues with installing Azure AD Connect on Windows 2019 pretty straight forward.
1.You need to install using a static password user i.e. need a domain admin example administrator user.
2. Working O365 global admin credentials.

As Deman said you need to "Add the suffix for  all the messaging domains that you will use to authenticate (in the Domains and Trusts console)".

Avatar of BBrayton


is there a way to change all the users in a custom OU with a powershell command to the new suffix.
And is there a way to put the .com as default so when we add a new user we don't have to change it every time. 
Yes, it is possible to address only one Organizational Unit. But it is probably better to update all users.
You can set a lot of users with a new Domain in UPN without doing script. If necessary, use "Saved queries".

User generated image

No, the suffix domains cannot be set as default.
You must use script to create or update user as wanted, or change your creation process to select the correct domain in the suffix list proposed when you create a new user.

Avatar of Saif Shaikh
Saif Shaikh
Flag of India image

Blurred text
View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
See Pricing Options
Start Free Trial
Avatar of BBrayton


Thanks for all your help
The PowerShell command worked Great!!
Microsoft Office
Microsoft Office

Microsoft Office is an integrated suite of applications that includes Outlook, Word, Excel, Access, PowerPoint, Visio and InfoPath, along with a number of tools to assist in making the individual components work together. Coding within and between the projects is done in Visual Basic for Applications, known as VBA.

Top Experts
Get a personalized solution from industry experts
Ask the experts
Read over 600 more reviews


IBM logoIntel logoMicrosoft logoUbisoft logoSAP logo
Qualcomm logoCitrix Systems logoWorkday logoErnst & Young logo
High performer badgeUsers love us badge
LinkedIn logoFacebook logoX logoInstagram logoTikTok logoYouTube logo