by JasonLion » Mon Dec 09, 2013 3:10 pm
There is still one simple move left, though it doesn't really get you anywhere. In block 2, you have left in some pencil marks for 4 which are not allowed due to the 4 in R3C1. That leaves the only possible locations for 4 in block 2 in row 1, which we can use to eliminate the 4 in R1C7.
After that, look for a naked triple in column 6, which should leave the puzzle fairly easy to solve.