Is there any way to add a sin line to all outgoing email?
I would like to add such a line to add a line to notify that the email is a legal one, and avoid blocking by webmail like Hotmail.
None that I know of. To avoid blocking I find it useful to keep an eye on my senderscore: https://www.senderscore.org/. Register for free and it will give you an indication of what may be going wrong if your score drops so you can work on it.
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