selective hydrolysis problem
If you use methanol as a solvent and add a suitable base, you should end up with the correct product, since any MeOH attacking the protecting group you want to keep will simply re-form the methyl ester, whereas the acetate will cleave to give the unprotected alcohol. 

You could potentially also achieve this using sodium methoxide/methanol to speed the reaction up, but standard potassium carbonate/methanol is usually just fine.