Painting walls stripped of wallpaper

[Pineman]

Hi, I want to paint some walls that have had wallpaper stripped from them. I know that I need to wash well to remove all the residual paste, but have 2 questions:

1. What happens if all the paste is not removed (i.e. I miss a bit)?

2. How long does it take for anything to go wrong if it is going to go wrong? What I mean is can I test an area and see what happens straight away or would it take some time for anything to happen?

Thanks in advance.

 

[LJW61]

If you leave any residue the paint there will 'pickle', youll see this within an hour of painting..Its possible to just scrape/rub this off when dry and repaint but always best to remove thoroughly in the first place - I use a green plastic kitchen pan cleaning (brillo) pad dipped in wallpaper paste solvent/remover disolved in hot water , rub the walls with this and sponge-off with warm clean water.. works a treat !
If the walls are really badly covered in paste or you just cant be bothered to spend a half day cleaning them them then its best to use lining paper

 

[Pineman]

Thank you LJW. I went down the lining paper route in the end.