Multiples??

Yes multiples.

Hate that.

10 minutes and its not correct... multiple solutions should be allowed!

Nice picture.

HINT all 4 corners are filled.

Has any one solved this. The last few dots make pattern in several multiples but I cannot get the correct solution.

Like Lupe said, all corners are filled, and every corner has a diagonal line moving inwards towards the middle of each 5X5 square.
(Example: R1C1-R3C3 for the top left 5X5)

Furthermore, each 2 sticking out from a 17 line have another diagonal line moving towards the edge of the 7 line that is closest to it.
(Example: R6C6-R10C10)

I hope that made enough sense to help if you're struggling, hard to find the correct phrasing.

Thanks.

Thank you Deathgrips.

Thanks.

Not logical even when assuming symmetry. Could not have solved it without hints. :( Horrible.

Frustrating, WAY too many solutions.