Please follow the steps to do this.
1. You need to create a Active Directory Distribution Group and add all of the users in your Exchange Organization to the group. If you create a Dynamic Distribution Group you can Specify the Organizational unit that has all the users in it. This is done through the Exchange Management Console or with powershell. You can see the Microsoft KB below on how to do this with powershell.
2. Within the UCCS Configuration Console go to Admin Settings
3. Select Data Collection
4. Select Exchange Configuration
5. Within the Exchange Configuration page fill out all the proper criteria and on the Target section add the Distribution Group you created in Step one.