Not LibreCAD, but Windows creates the duplicates.
With introduction of enhanced user access control (UAC) in Vista, Windows got a mechanism to avoid errors for applications which store and modify files in program folder.
With default settings, when libraries are in the program folder, LibreCAD does so.
UAC grants only read access for program folder to applications.
When an application writes to a file in program folder, like an INI file or in this case C:\Program Files (x86)\LibreCAD\resources\library\ Windows creates a virtual store in user space.
So look at C:\Users\YOUR USERNAME\AppData\Local\VirtualStore\Program Files (x86)\LibreCAD\resources\library\, there you will find the ghost files.
New created files are in virtual store only, modified files are found in both places. The original file from installation in C:\Program Files (86)\ and the modified one in the users virtual store.
Windows manages that you get the correct files from within the application.
But this applies only, when the application is not run in administrator mode.
When the application is started as administrator UAC is disabled and then only the files from C:\Program Files (86)\ are visible for the application.
Best option is to move the library somewhere to the user folder with write access and change the library path in application preferences.
Armin
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