Advice needed on damp proofing house, urgently!?

Hi, in march i had a damp course put in my houe (victorian terrace) our outside wall is below ground level by about a meter and had the worst damp problem imaginable. We had this fixed apparently, some areas are still damp and we have large areas of salt growing on the wall. What should I do? I cant afford to have the work done again or anything for that matter! any help appreciated!!