We run a hosted exchange environment, with many separate customers. Received an inquiry from a customer: "When we go to assign a task to a user, we can see many users from other companies" This is clearly not what we want. How can I prevent users from other domains/OUs from showing up in these user lists?

Have you create seperate address list for seperate domain ?Anil

Hi Carson, I think what you are looking for is address list segregation. Please refer to the following link, White Paper: Configuring Virtual Organizations and Address List Segregation in Exchange 2007, http://technet.microsoft.com/en-us/library/bb936719(EXCHG.80).aspx Please don’t hesitate to let me know if you have any questions. Best regards, Serena