Whenever I send an email (yahoo) from my phone, the body of the email is doubled one on top of the other. I only notice this when I look in the sent folder on the computer. When I look in the sent folder on the phone it looks normal (not doubled).

This is what my sent email looks like for clarification.

Hi,
This is a test.
-Dave

Hi,
This is a test
-Dave

Basically whatever I write is mirrored twice. Any ideas? Never happened on my droid 2 or 3.

Did some more testing and the recipient is not actually seeing doubles. It only displays doubles in the sent folder on the computer. Weird.

Re: Double messages

Did u ever resolve this issue? I've been dealing with the same issue for a while now. Curious.

Me too: just started with a Galaxy Young S6310 and Jelly Bean 4.1.2. Every Yahoo email I create on the phone looks fine in the phone's Sent folder, but shows duplicated content in the message in my PC's Sent folder. The recipient sees it just once. What IS going on?

This looks like the same issue as in thread 225389 "Yahoo Mail duplicating text inside each message on Droid RAZR" (last updated 02-18-2013). Any suggestions, please?

I have been having the same problem with my s4 mini. Has anyone found a solution for this?

I figured it out (finally).

Sign into your yahoo account on your computer.
Go to Settings>Viewing Email
Uncheck Enable conversations

Hmm... 'fraid that doesn't do it for me - Enable conversations has never been checked on my Yahoo.
Is there something else you might have changed at the same time?