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ADConnect not Syncing ProxyAccount email Alias from on Premise AD to Azure AD (i am using 1.1.56)

Copper Contributor

ADConnect not Syncing ProxyAccount for email Alias from on Premise AD to Azure AD (i am using 1.1.561.0 Version)

I have configured complete fresh configuration of Azure subscription for Office365 with Syncing On Premise AD to sync with Office 365 with ADConnect Version 1.1.561.0. 

this is completly new environment  i am setting up new user with three email Alias, I have sync on premise AD with Password sync option with my Office365 subscription.  so only option to add Alias is through On Premise AD by adding to ProxyAccount attribute.


I have added it to multiple user which has Exchange Online License available but it is not syncing any of email alias to my Windows Azure AD. any thought ???


6 Replies

Hi Amar,


Do you have any Exchange On-Premises ?


If no you will need to Prepare your AD with Exchange (Just Organizaiton Preparation) and then configure AD Connect whith Hybrid.

Hello Nuno,

thank you for your responce.  we are using Exchange Online with same Office 365 subscription.


do i need to perform any additiona steps on On Premise AD which is currently syncing with Office 364 AD with AD Connect?


Thank you,




Hi Amar,


If you do not have Exchange On-Premises, you will need to prepare the On-Premises AD to support sync.


Here how -


After preparation you will need to configure AD Connect to Hybrid Exchange.


With this steps you will have the proxy adresses synced from AD to Office 365.

Hello Nuno,

i performed same steps, prepare AD by following option with Exchange 2016 binary


1: Setup.exe /PrepareSchema /IAcceptExchangeServerLicenseTerms

2: Setup.exe /PrepareAD /OrganizationName:"<organization name>" /IAcceptExchangeServerLicenseTerms

3: Setup.exe /PrepareAllDomains /IAcceptExchangeServerLicenseTerms

4: reconfigure AD Conenct with Exchange Hybride Sync.


still no luck i tried to add mailNickName attribute with sync, only last thing i am predection that still i have not verified my domain. do i need to verify my domain to get it synced properly or this will sync all my ProxyAddress ...


Thank you,




best response confirmed by Amar Soni (Copper Contributor)

Hi Amar,


You have to validate your domain and have the UPN of your users to match your public domain to match each user to Office 365.


Then do a sync, after that your can add proxy addresses on-premises and sync to Office 365.

@Amar Soni  I am sure you have this figured out by now, but for those with the same issue. If you have already extended your AD schema to include exchange and this still happens where alias emails disappear on AAD. The key iI have found was when doing the step of adding a proxy address in AD be sure to add smtp: in front of the email address. It should sync to AAD after that.