Colour vision defect (colour blindness) is a very common defect among men. 1 out of every 12 men are affected by colour blindness. It is impossible to get into PSUs and IES (zexcept some posts) with a color vision defect. So, every though you got a rank in these exams but your chances of entering these coveted services will be close to nil.
It is considered as incurable since it is majorly considered a genetic problem. But it is curable!
If you are colorblind, there is no need to worry. Give us your contact details and contact us 2 months before your medical. We will guide you about the medical treatment required to get cured. Mail us on firstname.lastname@example.org for any help. Good Luck!