When you do a import or export request using the New-MailboxExportRequest or New-MailboxImportRequest CMDlet in Exchange 2010. It gave me an error.
Unable to open PST file ‘\\Server\Exports\Test.pst’. Error details: Access to the path ‘\\ExServer1\Imports\Test1.pst’ is denied.;
The Mailbox Replication Server (MRS) is running as LocalSystem it can’t access a network share. By adding the Exchange Trusted Subsystem group to the share permissions you will give the LocalSystem account and therefore MRS access to the share.