For the most part, this is now impossible. The reason being that the same methods that would allow this to work, would also make it possible for all kinds of ne'er do wells to do all kinds of ne'er do well type things.
Take a little time to research the fallout of this feature that people suffered at the hands of Outlook/Outlook Express. The Melissa worm is one that comes to mind, which had numerous variants, and crippled email systems the world over for the better part of a year. So while Microsoft was the last to get the hint and disable enabling scripts in emails by default, they did finally get the hint a few years back, and now you'd be hard pressed to find an email client that will do this. At least by default.
There's also the idea that not everyone to whom you make a recipient of this message would appreciate it. We tend to live in a rather narcissistic society, assuming that other people give a fig about what we do or have to say, when in reality, they don't. They might humor us if in our presence, but they're almost certainly nowhere near as interested as they make themselves out to be. And be honest, haven't you played along once or twice in your life?
So this is a bad idea on two fronts, technical and social, and best left forgotten.
Hi.
Every time I have to send a greeting, I suffer with the idea of preparing my own egreetings that use flash and are self executing for example sending a closed envelope via email that once clicked, will open up and some picture or video or just words will pop up. Please can you advise what I have to use in order to do this? I've spent considerable time searching online but found only scattered info that was not helpful at all for a beginner like me.
I'd really appreaciate if you could advise on this.
Thank you.

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