When saving the file, there will always be this notice, but in fact, it's a totally new file. and the file will be saved to a hidden folder appdata\temp\untitled...tmp. how could i solve this problem
I noticed that bug too. You just need to change the sketch name to anything other than the default name(sketch_nov05b in this case). The bug has already been fixed in the hourly build so there's no need to report this to the developers.