After reading various posts I decided not to use REGEX to check if an email is valid and simply use PHP's inbuilt filter_var function. It seemed to work ok, until it started telling me an email was invalid because I had a number in it.
ie name@domain.com works, while name2@domain.com doesn't.
Am I missing something or is the filter_var($email, FILTER_VALIDATE_EMAIL) really quite ineffective?