Hello @mberard and welcome to the forum!
The SEND-MAIL command can be used for command line testing. I’m not sure what the minimum is, but I’m sure that not everything there is required. Sometimes the command covers defaults better than docs:
C:\Program Files\Duplicati 2>Duplicati.CommandLine.exe help send-mail-level
--send-mail-level (String): The messages to send
You can specify one of "Success", "Warning", "Error", "Fatal". You can
supply multiple options with a comma separator, e.g. "Success,Warning".
The special value "All" is a shorthand for "Success,Warning,Error,Fatal"
and will cause all backup operations to send an email.
* values: Unknown, Success, Warning, Error, Fatal, All
* default value: all
C:\Program Files\Duplicati 2>
I’m pretty sure you’ll need at least --send-mail-to and --send-mail-url. Your email server might also need --send-mail-username and --send-mail-password unless you have one that doesn’t need authentication.
The command should give output beginning with
Whole SMTP communication, then actual email dialog.
If you want to see this happen on a backup, the same output can be seen at
profiling log level either in live server log, or with –log-file and –log-file-log-level, or (for commandline operations) –console-log-level.