Someone I know removed wallpaper and did not remove the adhesive. They primed and painted over it. Now … I’m trying to remove it all, and used a paint remover to start. Well, after scraping for several days, the surface is visible in some places, but the whole thing is very sticky, and will not dry. Do you know how I can remove this sticky substance so I can start over?
Wow, you have a job ahead of you. Check the paint remover label to see if it suggests a neutralizing agent. If so, use that first. If not, and it should, try small amounts of, in order, Water, Mineral spirits (paint thinner) or a household cleaner.
Then the fun starts. Sanding is your next project. Sanding this type situation is difficult due in part to the fact that you do not want to use a high speed sander. Sanding in one place will result in heating the residue causing a sticky mess on you sanding pad. I always tell my guys that it's not how hard you sand, but the number of passes you make over the area. In other words, make long smooth sanding strokes as opposed to short hard, wear yourself out, strokes. It'll be a job, but it is doable.
I'm hoping for his sake, that "someone you know" was not your husband.
Just wanted to reply to everyone who tried to help with the above. I ended up having to use a "paint and epoxy stripper" to clean the wall. Non of the other ideas worked … but I sure appreciate all the suggestions. Thank you very much for giving me some inspiration to keep trying.