Want to save my data on external hd

[leemaree]

Hello,
I have an external hardrive that hasnt been used for a while and now it gives me the f: not accessible the parameter is incorrect message. It says the disk is full but I know its not. Is it possible to save the data on it or should I try to reformat and lose my data.
kind regards Leanne

 

[leemaree]

ps i really want to keep the data