It happened the same thing with me, what I did:
First off, remove all transmission in your distro;
apt-get remove transmission-daemon
Second, obvious, install again transmission, but You need to install transmission-daemon tand the packages like transmission-remote, that’s what you will use.
apt-get install transmission-daemon
Stop the process:
/etc/init.d/transmission-daemon stop
Desactived the AUTH:
nano /etc/transmission-daemon/settings.json
edit this line:
rpc-authentication-required: false
Restart the process:
/etc/init.d/transmission-daemon restart/start
Execute this:
transmission-remote -l
If it work, none message will be shown. Now, you use a magnet link for test:
transmission-remote -a 'Magnet link'
Success message:
localhost:9091/transmission/rpc/ responded: "success"
Links:
http://www.webupd8.org/2009/12/setting-up-transmission-remote-gui-in.html
https://trac.transmissionbt.com/wiki