Good day!

We are in the process of exporting user mailboxes to pst using Exchange. So far using Exchange Management Shell the following tasks have been completed:

1. Given"Mailbox Import Export" Role Assignment to the user.

2. Created a shared folder "PST" and given "Exchange Trusted Subsystem" Read/Write permissions.

3. Next from EMS, I'll enter command "New-MailboxExportRequest -Mailbox user -FilePath \\mail\pst\user.pst .  

After the cmdlet is entered, I get an error as follows:

--"The operation couldn't be performed because object 'user' couldn't be found on 'DC_Name.domain'. 

--FullyQualifiedErrorId: 2020bd30,Microsoft.Exchange.management.ReciepentTasks.NewMailboxExportRequest.

Note: 'DC_name' is currently set as the Domain Controller of the Root Level Domain.  The user account exists in a sub-domain.

Please help how to go about it with this situation.

Thank you in advance.

Enter this command and then try again.

Set-AdServerSettings -ViewEntireForest $True