Here is how you can enable multi-instance mode for Notepad++ easily: Launch Notepad++. Select Settings and then Preferences from the menubar to open Notepad++ preferences. In the Notepad++ preferences, select Multi-Instance & Date from the left side list of categories., so if you use notepad++ -nosession -multiInst a.txt b.txt c.txt , it will open those three files to a single new instance, separate from any notepad++ instance already running., Multiple Instances of Notepad++. With this, holding shift and double clicking on the shortcut icon opens a second instance. Thanks for your feedback, it helps us improve the site., If you need MDI -mode Notepad++, there is no way to force it to start in multi-instance mode without the -multiInst parameter. If you can work with SDI -mode Notepad++ (like Notepad), it'll default to multi-instance mode just like the default Notepad on Windows: one window per file., You could create a .bat which runs two instances (ie, it calls c:\Program Files (x86)\Notepad++\notepad++.exe twice, at least one of which with the -multiInst option, or having the always-use-multiple-instances setting on in your Notepad++ config), and put that in your Startup folder (search the interwebs to see how to add something to the , There was a way to do this without opening two instances of Notepad++ and when I clicked on save, it made the saved changes in both instances of the opened file (whereas if I have 2 Windows of Notepad++ opened simultaneously, it will prompt me to either update or not update the second opened instance if the first one was saved midway.).