Go to /etc/Kannel/Kannel.conf and edit it like follows.
Here is my configuration file.
Here, to find the device in group smsc, I checked, /var/log/syslog. It shows when we plug a device in.
After configuration is done,
sudo bearerbox -v 0 kannel.conf
sudo smsbox -v 0 kannel.conf
If this not the first time and previous processes are still running, you need to kill them first. To do that,
first find the relevant processes by,
ps -ef|grep bearerbox
ps -ef|grep smsbox
Then kill them.
If the process ID is 914,
sudo kill -9 914
Now once you get bearer box and sms box running, try sending a message