On numerous occasions, I have tried to fillet between two lines of a fairly short length, or very acute angle. The value set for the fillet, before I have a chance to enter my own, is too large to be successfully created. Rather than failing gracefully and reverting to '0', so I can enter a smaller value and try and find one that works, it simply won't allow these two lines to be filleted and cancels the tool. The fillet option for sketches should fail in a manner more like that for solids, where you can keep entering measurements until you get a result that works.
Unfortunately I don't have a specific sketch on hand that shows the behaviour in a reproducable way.
Thanks,
Nick
Thanks for reporting the issue!
I got some difficulties on reproducing the fillet failure too, but finally found a failure on fillet an acute angle. Anyway, I will pass it to development team to investigate. If you encounter the issue again, feel free to send it to sally.yang(at)autodesk.com. Thank you!