How to split one Organizational Unit (O.U.) into two?

Problem: This knowledge-based article targets scenarios where there is a need for splitting 2 Exchange Mail Domains that reside under a single Organizational Unit into their respective Organizational Units OR this helps in separating one organization from an existing Organizational Unit.

Scenario: Let’s assume there are 2 Exchange Mail Domains ( Company1.com, SubCompany1.com ) that reside under a single O.U. named OU-Company1 in Active Directory.
 
                          OU-Company1
 
             Mail Domain # 1 = Company1.com
             Mail Domain # 2 = SubCompany1.com
 
 
Now at any point in time, SubCompany1.com which is a subsidiary of Company1 may grow into a big entity and may want to maintain a distinct identity. It can move its AD Users, Groups, Contacts, etc. into a separate Organizational Unit in the Active Directory. The following diagram shows what the resultant OUs in AD will look like:

To achieve the goal, follow the below steps:
  1. Login into the HC panel and navigate to the menu Provisioning >> Exchange Organizations and click on Create Exchange Mail Domain button.
 
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  1. Open SQL Management Studio and open HC10 Database as shown below.
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3.  In the HC10 Database, remove 2 records from tables tblExchangeMailDomains and tblProvisionedResources by making IsDeleted = True against the existing SubCompany1.com in HC Database.

 
DELETE FROM tblProvisionedResources
WHERE RecordID in ( SELECT MailDomainID FROM tblExchangeMailDomains WHERE SystemName = ‘SubCompany1.com’ )
AND ProviderID in ( SELECT ProviderId FROM tblProviders WHERE DisplayName in ('MS Exchange 2010','MS Exchange 2013','MS Exchange 2016','MS Exchange 2019')
 
4. In HC10 Database open the table named tblExchangeMailDomains and rename test.com to SubCompany1.com.

5. Remove the test.com accepted domain record from Exchange Admin Center too. Search for the test.com domain and delete it from ECP. See the below screenshot for clarification.

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6. Open Active Directory Users and Computers using command dsa.msc and add uPNSuffix value as SubCompany1.com against SubCompany1 OU as shown below.

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 7. To apply Address List Segregation for the new Address Book Policy objects on this SubCompany1 organization, follow the steps below:


This utility can be executed on the HC server or on the Exchange server. Before executing the HC import utility, there is a configuration file with the name "ImportExchangMailboxesAndListsIntoOrg.exe.config". Enter the details of Exchange server and administrator credentials in this config file.

After the execution of the import script on command line, below options will appear:
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Following are the required Inputs for this utility:
  • Enter Mail-Domain Name: Enter SubCompany1.com as Mail Domain name.
  • Enter Organization-Name: Enter SubCompany1 as the Organization Unit in AD.
  • Enter Organization-OU: Enter the OU path (distinguishedName) here.
  • Enter Domain Controller: Enter the DC details or skip it without providing the details
This will separate the desired SubCompany1 OU and its accepted domain from an existing OU to its own OU in the HC panel. For any query regarding the instructions, feel free to contact us at support@hostingcontroller.com

Note: In the above instructions, names of organizations are merely examples which can be replaced by actual Organizational Units and Mail Domain names.