Paint peeling problem

hargo

I have been doing up a house in France which was papered throughout. I removed the paper and with great difficulty removed the paste washing and scraping over and over. I have successfully painted most of the wall however one wall is causing a problem in that the paint isn't adhering properly and lifting on second coat.
Do I try and remove the paint and bond the wall(I have read pros and cons already in the use of polybond ) or what?
I am also about to repaint the outside of my house and there is one small section around the hall door where the paint peels. This was the same last time i painted and i removed all loose paint and scraped walls but paint is still peeling. Anything I can do to prevent this? There is a hairline crack in the wall at this point.
Any advice welcome.

game4it70

for your wall inside sand wall first then apply a coat of oil based stablizing solution.make sure its not water based as its useless.use a short pile sleeve for your roller.
then paint with normal emulsion.
for outside scrape loose paint and fill crack with painters chaulk.use an then use the same stablizing solution on this prob.
again then paint as normal.
ps. try use dulux weather-shield on the outside.its dear but by far the longest lasting.
best of luck.