TOPIC: Empty message body Error

I have Joomla 2.5 installed and running the latest DT Register 2.8.6c

I went into the Config and edited the thank you email and it now requires me to enter a email address as the sender email. I entered a email address and now when i register, it gives me this error message: Empty Message Body.

Also, I am not getting the confirmation email that the user should get.