Quote:
Originally Posted by Mugwhamp
Understood, but my question doesn't relate to speed, it concerns spam scanning. Is POP3 email scanned by FM's engine, while email forwarded to FM is not? That seems to be the implication in the quotation above.
|
Yes, I think the best answer as to how spam scanning is done for POP'ed email, should be answered by Fastmail support. My tests seem to indicate, however, that:
- Normal SpamAssassin scanning is performed and spam/nonspam is processed based on the scoring as usual.
- The special checks for DMARC which add 8 or 15 points to the spam score when DMARC fails, are not done. This is because the checks for valid SPF and DKIM are not performed for POP'ed email, and DMARC depends on those.
- The check for SPF cannot be made in any case since there is no "sending server" to Fastmail, and it would not make any sense for Fastmail to use the server it POP's from (which would normally fail anyway).
- I think a DKIM check could theoretically be made at the time of POP'ing the email, but Fastmail does not do it. It would anyway lead to complications if you POP'ed old emails from an account (perhaps as a bulk transfer), because encryption keys might change over time.
Forwarded email is always scanned, including DMARC.