How to filter based on User-Agent header
I am attempting to filter MailChimp spam, which usually contains a User-Agent header of "MailChimp Mailer." I have added a filter header of "User-Agent" and a filter of "contains" "MailChimp" with the instruction to move the email to a separate folder I have set up. When I run the filter on a folder which I know contains such emails, nothing (visible) happens, and the filter log is empty. What am I doing wrong? Thunderbird 60.5.3, Windows 10
Modified by stioudson
Chosen solution
Before running a filter, it's often worth performing a search to confirm the syntax. Right-click a folder, Search Messages..., and add User-Agent as a Custom header, as with filters. I tried it here and found matches. Does it work for you? Try it with a simpler filter action such as star or tag.
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Chosen Solution
Before running a filter, it's often worth performing a search to confirm the syntax. Right-click a folder, Search Messages..., and add User-Agent as a Custom header, as with filters. I tried it here and found matches. Does it work for you? Try it with a simpler filter action such as star or tag.
Thank you. This answer pointed the way. Also, by using "view message source," it turns out that X-Mailer is a better header to use.