Why do I loose power steering and brakes when i press the brake pedal? on 1996 Chevrolet Astro

I have just replace the power steering pump. We drove the vehicle a few miles and lost both power steering and brakes again when we pressed the brake pedal.

Asked by for the 1996 Chevrolet Astro
if u nave hydarboost thats your problem
1 more answer , 2 more comments
possible hydro-boost issue.
I have not worked on this type of system before. Please explain the hydro-boost system. I do have some mechanical training. Are you saying the hydro-booster could be bad? you have a vacuum brake booster OR a metal one with a lot of pipes and fittings?