How do I check/track the delivery of an email?
It sounds like you're referring to a delivery receipt.
Many email programs have the option to "request a delivery receipt". Then, when the recipient receives it and clicks on the email, they will have a little box asking whether to send or not send back the receipt.
Personally, I always click no on sending back the receipt so the receipt won't be sent. For me, it's a privacy issue. But other people will click yes. It all comes down to personal preference on whether they want to acknowledge that they read it.
From what I have seen, it doesn't even ask on any webmail sites either, just ignores it.
Just like 'recall' message, been bitten because someone choose not to let me 'recall' the message, instead they read/opened the message
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