@VAVoices ,
That shouldn’t change without you intentionally changing the setting.
Recently, there was another user who discovered that “mysteriously changing settings” were caused because they had two different copies of Notepad++ installed with different config files, and sometimes one was run and sometimes the other. You might want to check for multiple copies of notepad++.exe on your computer.
The other thing I see is that you are running in Admin mode in your screenshot: it may be that in admin mode, Notepad++ is able to write the config files when it exits, but if you run in non-Admin mode that the user you are running as does not have write permission to the appropriate config.xml, so it cannot save the settings, so the next time you run, it has forgotten that you don’t want that option on.
So, if you don’t have two copies of Notepad++, I would suggest looking into permissions of %AppData%\Notepad++\ directory and the files inside. You might find it easier to exit all copies of Notepad++, then use Windows Explorer to go into %AppData%\, and rename Notepad++ folder (maybe to Notepad++.old). Then re-run Notepad++, making sure it is not run-as-admin; this will recreate the %AppData%\Notepad++\ folder and all the critical configuration files that belong there, with everything set back to defaults (and the default for .bak is off, which is what you want), and the permissions should be right for your normal user to be able to save changes to the Notepad++ configuration when it exits.
