Restarting the workstation might do it?
I know of no way to prevent the message. I know of no trust center setting for safe mode.
Why can they not say "no."
Why are you running Word from the server rather than the workstation?
This forum is primarily for end users rather than system administrators.
You might want to cross-post on Tech net.
For cross-posting etiquette, please read: http://www.excelguru.ca/content.php?184
https://social.technet.microsoft.com...ome?forum=word
and perhaps
https://social.technet.microsoft.com...t=lastpostdesc