Replace Windows Notepad with any text editor easily, using Notepad Replacer
Windows notepad is a fine little tool, however several other plain text editors are equally fast and far more powerful. My personal favorite is Notepad Plus Plus, and I must say I was frustrated that some programs preferred to run the Windows notepad no matter how my file associations were configured.
Notepad Replacer is a free and light utility that configures Windows to run your favorite text editor always, whenever Windows notepad is called. The program won’t replace any system file and permissions. It also won’t remain open to perform the replacement whenever it is needed. It will just make a registry change upon installation. First you are asked where to install the program, then the path of the text editor you’d like to use instead of Windows notepad, and that’s it. The program makes the registry change and remains closed forever!
In case you prefer to make yourself this registry change instead of using the Replacer, here is the line you need to execute as administrator in the Command Prompt (Replace the path to Notepad++ with the path to any editor):
reg add "HKLM\Software\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\notepad.exe" /v "Debugger" /t REG_SZ /d "\"%ProgramFiles(x86)%\Notepad++\notepad++.exe\" -notepadStyleCmdline -z" /f