I have never used kannel. However, looking even briefly at the user-guide above suggests that you have to
edit the kannel.conf file. Presumably you know how to edit a file. If not, try pico
(for pure text editing)
for a GUI. (Or vim
, if you want a real editor that will grow with you). Looking at the manual it seems you may need to create the kannel.conf file before you
use the program.
The error you posted merely means the program can't read the file, either because it's not there, or because you don't
have permissions set correctly.
Please post the output of the following command
ls -l /etc/kannel/kannel.conf
That will tell us if the file does not exist or you have a permissions problem.