Opening a text file at a certain line (shortcut)

You'll need to use the command line option listed in the other answer.

And then add a Shortcut key (aka Hotkey) to that Windows shortcut like so:

1. Make a shortcut to the program itself. You can do this by right clicking somewhere (desktop is easiest, but it doesn't really matter where) and choosing New -> Shortcut. You can also just find Notepad++ in the Start -> (All) Programs menu, right click on the item, copy it from there, and then paste it.

2. Right click the new shortcut you've made (not the one in the Start Menu), choose Properties, and then go to the Shortcut tab. In the Target box you'll have something already there like "C:\Program Files (x86)\Notepad++\notepad++.exe" You need to add your file you wish to open after the quote marks, and then -n## (replacing the #s with the line number). The target box should read something like "C:\Program Files (x86)\Notepad++\notepad++.exe" c:\users\username\desktop\test.txt -n73

3. Stay on the Shortcut tab: there is a box for editing the Shortcut key. Click in there and type a letter. It will automatically add Ctrl+Alt to the front of it, and that is your shortcut key. I'm unsure if you can use any other combination keys for the shortcut key.

You need to use the following command-line option (where "#" represents the line number):

-n#

The complete list of command-line options for Notepad++ is available in the project wiki:

Controlling Notepad++ at startup by passing it Command Line Options

To open multiple files each on a certain line with Notepad++:

// for each file (as command line):
notepad++.exe -multiInst filename -n#