it's possible that you did not exit the editor properly, so that the .swp file was not deleted. one reason for this may be that you accidentally hit ctrl-z (suspend process) while editing a file. this is a common problem, as i've observed, with people new to linux. you can see your suspended jobs with the "jobs" command, and can un-suspend the last job by putting it in the foreground again with the "fg" command. this all needs to happen before you log out and thereby (probably) kill those jobs.
if you cannot resume your editing session as above, you can follow the the instructions of the error message, and attempt to recover your changes with "vi -r", or just remove the .swp file (with "rm /path/to/.swp/file") and work with the file that you have saved.
in future, you might make the subject of your thread more descriptive, e.g. "vim swap file prevents editing" rather than "unexpected message".
Last edited by Berhanie; 11-20-2012 at 12:51 AM.