Can I put Flash in HTML messages?
Adobe stopped supporting Flash in 2020. While it may be possible to embed Flash in an HTML message, we do not recommend doing so.
For security purposes, most email programs will block Flash from running in messages. This would cause your messages not to render properly, and may result in spam complaints.
If you have a Flash video or file that you want your subscribers to access, you may want to embed it on a page of your website and send your subscribers a link to it.
You may also wish to take a screenshot of the Flash file or video, add the screenshot to your message, and hyperlink the image to your website.