How do I add my own domain to Exchange trusted senders?

Question

PowerShell

There is an Exchange mail server, suppose the domain: contoso.com
The problem is that some of the letters of internal mail users end up in the junk folder! Adding your own domain from the client side (Outlook 2010) is essentially impossible, because he moves away from there almost immediately. There are no filters on internal mail.
Question: how to massively solve this problem from the side of Exchange?
Maybe so? If yes, what are the consequences?
getmailbox | Set-MailboxJunkEmailConfiguration -TrustedSendersAndDomains @{Add='contoso.com'}