Not always saving when exporting object to stl

I do all my designing on an Apple ipad but when it comes to export objects to STL, I like to use the windows version on a computer with a Windows 10 fresh reinstalled computer.

But every time I do that, I have to watch for a bug not saving the STL file. Here is the sequence.
I open Windows Explorer on one screen, watching the directory I will save files in. On the other screen with Sharp3d, I select the object, isolate it and then export. As I click to save, I see the file appear in windows explorer for a second and disappear. I export again and save, then the file stays but i can happen that it takes 3 tries to save it. There is no error showing up on screen. Usually it happens on the first export, then it holds on with rare re occurrences. Next day, it happens again.

Welcome to the forum, Richard!

I have found on the iPad when exporting STL (or better yet 3mf) files that the directory sometimes jumps around, and an export goes to the wrong place if I’m not paying attention. Perhaps Windows does the same??