Hi @ilianko ,
Does exporting all mailboxes have this issue?
"PST file is without errors" means that you can import the .pst file to mailbox and get the complete mailbox data?
Please try to following steps:
1.Please try to restart the Microsoft Exchange Mailbox Replication service.
2.Please try to run the following command to view the health and status information about mailbox database copies.
Get-MailboxDatabaseCopyStatus
3.Please run the following commands to remove all mailbox export request then create an export request to export only one mailbox, then check the status again. If the status is normal, please check whether the script you are using supports Exchange 2019.
Get-MailboxExportRequest -Status Completed | Remove-MailboxExportRequest
New-MailboxExportRequest -Mailbox <> -FilePath <>
In addition, according to my test to export the mailboxes in Exchange 2019 and running the " Get-MailBoxExportRequest" and " Get-MailboxExportRequestStatistics" command lines, the results obtained are normal.
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