Ошибка в скрипте Send-MailMessage

Question

$SmtpServer = "smtp.server"
$From = "myself@email"
$To = "friend@email"
$Subject = "Weekly Admin Points Backup"
$Body = @" 
Hello.... 
"@
$attachment = "F:\AdminPoints.docx" 
Send-MailMessage -To $To -From $From -Subject $Subject -Body $Body -Attachments $attachment -SmtpServer $SmtpServer

Я получаю эту ошибку при попытке выполнить простой скрипт PowerShell с вложением:

 Send-MailMessage : The process cannot access the file '*<Filepath>*'    because it is being used by another process.

At <*script>*.ps1:9 char:17
+ Send-MailMessage <<<<  -To $To -From $From -Subject $Subject -Body $Body -Attachments $attachment  -SmtpServer $SmtpServer
    + CategoryInfo          : NotSpecified: (:) [Send-MailMessage], IOException
    + FullyQualifiedErrorId : System.IO.IOException,Microsoft.PowerShell.Commands.SendMailMessage 

Любые идеи, что я могу сделать, чтобы решить?