I have not run into this problem. This made me think of the first tech class I had, where I was playing Freecell on our Windows computers. If I paused for a second in my game, the cursor would slowly move up to the corner and click the X. It happened several times! I went up to the teacher and said I suspected the computer had a virus that was closing Freecell. Of course, he was closing Freecell. 'Remote assistance' is often enabled by default in Windows these days!
In this case, my teacher is perhaps Windows Defender, and the rest is perhaps a pointless side story. If Windows Defender is enabled, try adding an exclusion for your C:\mango directory. Depending on your File settings C:\ProgramData might be hidden to the searches you're running. If not Defender, might there be another Antivirus program getting ahead of itself and deleting your C:\mango?
After that, if I was facing this problem, I would try (in no particular order)...
A. Downloading Mango again
B. Trying it without modules
C. Checking out the "Event Viewer" for interesting logs
D. Having a text document opened in an editor, and saved in your C:\mango directory.
E. Using the default env.properties
F. Booting on a clean database
G. Disabling networking
H. Trying a different directory
I. Watching C:\mango disappear in Windows Explorer (it'll live update!)
JK. Switch to linux