How to migrate Azure AD synced user from synced onpremis user account to another

Hi peter1640,

The process you're looking for is hard-matching a user with Azure AD Connect. First you need to disconnect the on-prem account in the AUS AD from Azure AD. This can be done by simply move the on-prem user account to an OU that's not synced to Azure AD. Then you need to take the following steps:

1. Make sure you have the necessary permissions to manage users in Azure Active Directory (Azure AD) and to perform a hard match.

2. Identify the user you want to hard-match in Azure AD.

3. Once you have identified the user, you will need to find the newly created matching on-premises user account in your local Active Directory in the UK. 

4. Once you have identified the matching on-premises user account, you will need to update the user's ImmutableID attribute in Azure AD to match the objectGUID of the on-premises user account. This can be done through PowerShell (Set-AzureADUser email address removed for privacy reasons -ImmutableId "ObjectGuid from on-prem account") 

5. After updating the ImmutableID attribute, you will need to run a Delta Import sync in Azure AD Connect. This will perform the hard match and link the Azure AD user account with the on-premises user account.

6. Verify that the hard match was successful by checking the user's properties in the Azure AD portal and in Active Directory Users and Computers. The user's account should be linked and the user should be able to sign in to both on-premises and cloud resources using the same set of credentials.

Note: It is important to ensure that the user's on-premises and Azure AD accounts have the same user principal name (UPN) and that the UPN is set to the user's email address. This will ensure that the user can sign in to both on-premises and cloud resources using the same set of credentials.

Let me know if you have any additional questions.

Regards,

Ruud