Pave set is like a silicone gell coated very fine sand. Instead of using sand to sweep into your paving and then compacting you use pave-set, compact the paving and then hose over it. The water then activates the pave set. It then dry hard and locks the paving together. Pave Lock is a another similar product.
I have found myself in a similar situation wher I didnt sweep all teh pave set and there are bits of hardened pave set stuck on top of pavers. I was wondering if either hot water or acid (as suggested previously) worked for the Rixter If not did you find any other solution that worked for you?