@Ryan_N wrote:
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It's easy to assume that these email can be intercepted before they get to anyone, but it is near impossible to do so. The rate and different varieties are constantly changing.
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The email headers shown below are from a phishing email I received to my Inbox and server side filtering could, and should, have caught it and flagged it as spam.

(0) improbable source for Virgin Media company email
(1) display name, email address username, and email address domain
(2) subject; with no attempt to obfuscate the purpose
(3) a remote resource link that does not match the source link
The detection of 3 should have been enough to either flag this as spam or at the very least a candidate for further scrutiny and combinations of 0, 1, and/or 2 enough to confirm it.