Batch files default to being opened in editor rather than executed

This is on Windows 10 x64 creators edition. I’ve created a batch file and placed it in C:\Users\Nick\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Start-up, but every time I start the machine and login, I find that instead of the batch file getting executed, it opens in Notepad++. Same thing happens when I double-click a batch file in Windows Explorer. How do I change the file association so that batch files get executed. By design, Windows doesn’t show the Open With menu option for executable files (.bat, .cmd, .exe, etc) when you right-click on them, nor does it show the Change button to allow you to change the default program in the right-click file properties for executable files, so I can’t change the properties that way.