Help Email sending twice (not gmail)

[frankenbeanie]

I have an Outlook (hotmail) account synced to my phone and whenever I send an email through that account, it ends up being sent twice for some reason. When I look in my "sent" folder, I can see the email was duplicated and sent twice, every single time. It only happens when I send emails on my phone. If I send it through another device (desktop, laptop, etc.), it works just fine.

I'm not using an app for the outlook account. I just selected "Add Account" and "Email" from the Settings menu.

I'm on Android version 4.3

Any insight would be much appreciated!