There have been a number of messages here on the fact that Etcher has access problems when running on Windows - because it needs to be run with elevated privileges.
Back when I worked for H&R Block, we ran into this issue when developing software for Win Vista +.
The solution is to include a “manifest” file in the root of your build. I do not know what the current format for the manifest file is now, but there is a key called “request admin” (or something similar), that causes the executable to request elevated privilege when run.
This will cause Etcher to always request admin access before running - allowing Etcher access to the underlying hardware.
This can be done with both the installed executable and the portable executable file.
What say ye?