Spammers use a "web beacons" approach routinely to verify that e-mail addresses are valid.

Question

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Spammers often use web beacons (also known as tracking pixels) to confirm that an email address is active and being checked by a human. When someone opens an email that contains a web beacon, it sends a signal back to the spammer's server indicating that the email was opened, and thus the email address is verified as active. This is a common tactic used in email marketing and spam campaigns.

Spammers Use a "Web Beacons" Approach Routinely to Verify That