Watchguard V10 User Manual page 316

CHAPTER 10: Using Proxies
Masquerading tab
This tab allows you to masquerade domain names and
message-IDs for incoming SMTP messages.
Masquerading domains allows you to present all email as
if it originates from a single domain. Masquerading mes-
sage-IDs allows you to replace the message-ID SMTP
Header with new IDs.
Masquerading is generally only useful for outgoing SMTP.
Domain Name
284
Type a domain name here to replace the domain
names for incoming messages with the specified
domain. For example, if you type
"watchguard.com," then to your users it will
appear that all incoming email is from senders at
watchguard.com.
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