My Outlook started sending empty emails. The really annoying thing was that I could spend an hour composing the perfect email, hit Send, and it would strip the content before sending. The email in the Sent folder was devoid of content too. Gone!

I dunno if the following really fixed it, or if it simply went away on its own at the same time:

• File > Options > Mail > Compose messages in this format:
  • Set it to Rich Text
• Send an email. It works!
• Set format back ot HTML. It still works!