WinXP SP3, Npp v6.5.4
argument -c2 does not work.
"C:\Program Files\Notepad++\notepad++.exe" -c2 -multiInst -nosession CommandLine.html
If I specify the line number (-n1) then works

If you do not specify a line number, it is necessary to specify the position in the file from the beginning, ignoring the line.