Is there any way to send a message that will “revert” to plain text if the recipients email tool can handle “formatted” messages?
This is an interesting question, and from our research the answer seems to be “no.” That means you need to send emails that “collapse” into text-only without changing the look (i.e. no images, no bolding or centering or other formatting). Or just send text-only emails to begin with. The companies that develop email tools are still catching up with the fact that people want to send formatted email, and in the meantime there is no way to assure that all your email messages will look like they do on your end…unless you use plain text only.