Found a post that is a few years old that the user had the same issue. I have a new Joomla 3.4.5 site that was working great. I install JomSocial and now when a new member registers I get a system email that simply says this:

COM_USERS_EMAIL_REGISTERED_NOT​IFICATION_TO_ADMIN_BODY

Support said this was a Joomla problem but I cannot find anyone that has had this problem. I opened a support request anyway but figured since everything was working fine until I installed JomSocial I would as here too. Why is this now broken when it was working fine prior to the install of JS, any clues?

Hi Kevin,

If you registered with Joomla com user and you get this issue, so this is joomla problem, please you contact to Joomla forum,

I suggest you register via Jomsocial register page, the email notif is working fine

Yes, the register worked, it was the email I got as an administrator that was messed up. I took a stock Joomla site and did a copy and replace of all the core language files because I think some of them were corrupted somehow? Anyway all is good now, thanks...

you're welcome..