Removing rTorrent session data
This is easy task as well, but you need to ensure first that rTorrent is not running. As soon as ruTorrent gives an error of something like bad link to rTorrent, you may proceed to delete session data.
Deleting via shell
First connect to shell, see Connecting using Putty. You may also use kill command to kill rTorrent, or Accessing rTorrent console to shutdown rTorrent, ie. by killing screen window using ctrl+k on command prompt type:
cd ~ rm -rf session/*
First command will move you to your homedir if you are not already there, second will delete the session data.
Deleting via file manager
First ensure rTorrent is not running. Then proceed to your homedir subdirectory session, choose all files and click delete.