I believe MultTerm 2014 cannot access termbases on a MultiTerm 2009 server. MultiTerm may have stored a link to such a termbase. Go to C:\Users\"user name"\AppData\Roaming\SDL and rename the folder SDL MulltiTerm to xSDL MultiTerm so that the folder will be recreated the next time you start MultiTerm.
Thank you very much for your advice!
I have done what you suggested, but, unfortunately, it doesn't help.