Could you solve the problem?
I'm having the exact same problem. I also tried the workarounds you described and others suggested, but the problem still exists.
Also it seems system dependence. I've run my app on two different systems and the problem only occurs on on of them, which is a fairly new and fast system with an AMD 16 core threadripper. On the other, older systems (10 year old Intel i7) the problem has never occured. Both systems use Windows 10 64bit, R2020a.
I've also gone through the trouble to implement my own simple file dialog as a workaround, but the error still randomly occurs.
Another observation: The problem occurs seemingly more often or maybe only when the runtime of the line of codes following the file dialog are very short. To suppress user interaction after choosing the file, i'm starting an uiprogdl progress dialog directly after the file is chosen and close it after the line of codes are completed. So maybe the problem is the short progress dialog...
I'm running out of ideas. Any help would be very appreciated.
