No idea where to start on this.

All but the corners of both diagonals(r1,c1 to r15,c15 and r1,c15 to r15,c1) are filled in.
If more hints a needed I'll give some.

Thanks, Teesea.

Thanks Teesea for your hint - impossible otherwise!!!!

Thanks for the hint - it helps a lot!

I don't understand your "help".

Make an x from corner to corner. except the 4 corners themselves.

Omg you hints are wrong. . .. there is no way to solve this god damn puzzle ive been trying for about a week npw -.-.

... I'm sorry my mate explained the clue to me and i solved it. good looking puzzle.

The hint to make an x minus the 4 corners themselves was very helpful :) thanks kaiko!!