Ps3 'Failed to install trophy set'

[Byrnezy]

When i begin the game Demon's Souls the message comes up 'Failed to install trophy set. Please shut down game and try again' I have done this multiable times without sucess. I have the first version of the Ps3 system when it became available. I thought the problem was to do with the psn network being down but that proved untrue. I can play the game if i creat a new profile but im afraid of this problem happening again and i dont want to lose my save data (this problem has happened on 2 users). Any advice you can give will be very helpful?