I meant to run just this command from the Command Prompt:
"cmd.exe" /c echo D:\Programs\3ds Max 2018\Plugins\efewfwf.msi > "C:\Users\Andrey\AppData\Local\\Ornatrix3dsMaxSetupFilepath.txt"
or even just
echo D:\Programs\3ds Max 2018\Plugins\efewfwf.msi > "C:\Users\Andrey\AppData\Local\\Ornatrix3dsMaxSetupFilepath.txt"
The most likely reason is that this file C:\Users\Andrey\AppData\Local\\Ornatrix3dsMaxSetupFilepath.txt is not accessible for writing. I have no idea how can this happen, the AppData\Local directory usually has full write permissions for the user it belongs to. You are logged in as Andrey, right?
The message you get at the start of installation points in the same direction, that some files are not accessible for writing.
It might help to reboot your machine and try again. After rebooting first check if you can write to that file, C:\Users\Andrey\AppData\Local\\Ornatrix3dsMaxSetupFilepath.txt: if it doesn't exist, create it, if it does, open it in Notepad, erase its contents and save it. Then run the installer with logging.
