Using SP 2010 Enterprise our User Profile Service has been working fine for over a year now. All AD users are present.
I have recently created a search center with a people search.
The problem is that all accounts including service accounts and disabled accounts\former employee's are being displayed.
To get around this I changed the sync settings in the UPS so only the AD OU's that has genuine users in were synchronized as by default we had set it to search all of AD. After this I synced the UPS thinking this would solve the problem however I still have exactly the same amount of profiles!
I cannot delete the unwanted profiles manually as there are over 500.