For years, I’ve been importing and exporting mailboxes with relatively no problems, when I started getting this error when exporting a number of mailboxes: [PS] C:\Windows\system32>New-MailboxExportReqeust john.doe -FilePath \\server\share\john.doe.pst Unable to open PST file ‘\\server\share\john.doe.pst’. Error details: Header file length is zero. If this file is from a previously failed pst export, please delete the file and resume the export. + CategoryInfo : NotSpecified: (0:Int32) […]