Daily Jigsaw Jammer won't load after upgrading from 8.1 to 10.

me too. Happened following a reinstall of Windows 10. Seems to only effect the Daily Challenges and the Events. Additionally, MS Jigsaw daily games won't finish loading.

I am also having issues with the daily challenges not loading. They are in a constant state of downloading. I am using this game on Windows 10. With windows 8.1 I did not have this issue and it only started after I upgraded to 10. I have tried to do all
the options that were given but it still is stuck.

Me too I can't get the 1st and the 3rd jigsaw jammer to load

I lost Jigsaw Jam collections 2 and 3 as well.

After uninstalling/reinstalling Jigsaw, I've now also lost the stats for Jigsaw Jam collections 2 and 3.

Oh well, at least I still have all the Jigsaw Jam Achievements.

In the plus column, my Daily Challenges sounds (the "Coin Drop" and so-forth) now work correctly. This is a problem I've seen come and go with other games (such as Minesweeper and Solitaire) on Windows 8.1. I never had those problems with Windows 8.0,
and this was a big reason I delayed upgrading to Windows 8.1 for nearly half a year. The mid-September updates fixed the problem in Minesweeper and Solitaire, and the just-released update for Jigsaw fixed it for Jigsaw.

Also, despite some of the underlying stats still being wrong, I'm now getting proper credit for completed collections in Classic Jigsaw. The stats still say, for example, that I've played 10 and completed 8 Expert puzzles (I actually completed all 10) but
now I'm being given credit for completing the collection in Expert difficulty.

Problem solved. Uninstalled Microsoft Jigsaw and re-installed. Everything is working just fine.