user registration verify link & approval

Hi, not sure if this is a joomla issue with my website but when a user registers, they are then directed to a blank page (still showing my template) they then receive the verification email, but when clicking the verify link it takes them to a blank content page again and then i get the 'registration approval' email, but when clicking that link it does the same as above and then the user receives the 'account approved' email. Any ideas would be appreciated, i have searched on the joomla forums but can't see anything related so will also post on there. Regards James