admin email not working

I am not receiving any admin emails when a new user signs up, adds a listing, etc. etc.
I have set up emails for each email function IE. “welcome email” via the email setup area.
The interesting thing is that I AM receiving the emails FROM the admin to the user email account IE. welcome email will be sent to new user from the admin email address. Also, when I send test emails from the email setup page to an email address other than to admin email, I receive the emails just fine.

I tried deactivating all plugins, etc…nothing seems to work. Also, I thought it maybe be a security feature that is preventing emails being sent from admin@mydomain.com to admin@domain.com HOWEVER, if I use outlook to send myself an email, it works… very bizarre.

Any help is appreciated.