Notepad++ comment every opened file

Question

Using Notepad++, how would I add a /* to the beginning of the first line of every opened file, using the replace tool?

My failed attempt:

Find what: /^(.*)$/m

Replace with: /*$1

This results with 0 hits.

Answer 1

How about:

Find what: ^.*$
Replace with: /*$0

Check Regular expresion and Dot matches newline