While saving Exchange mailboxes data into Outlook Data format, Powershell commands “New-MailboxExportRequest used.
In addition, the role is not assigned to any role groups by default.
Thus, in order to use the Export Powershell command, you require adding the Mailbox Import Export role to the role group.
But, If the MS Exchange trusted subsystem group does not have enough read and write permissions, then it leads the following error message:
[PS] C :\> New-MailboxExportRequest “userabc” -FilePath “\\MYSERVER\PST\userabc.pst”
Unable to open PST file ‘\\MYSERVER\PST\userabc.pst’.