I have the same problem with a standalone computer Windows 10 Version 1803.
When I open a Dataflex application, it crash after 1 minute and the .exe file and the .ini file bound with it disappeared.
The only solution I found is to desactivate the "protection in real time" by McAfee.I don't know if it's possible to add some exceptions in the list of files to be protected because all Dataflex applications have the same problem.
I have downloaded the last Windows update but I still have the problem.

Jacques