External Hard disk problem?

[uknowist]

Hi my external hard disk has been working fine but today its not reading properly, it willl load up fine then the folder will close by itself and i get a windows error saying format E:/ (which is my external HD) any ideas whats causing this? isit nackered for good?

thanks

 

[uknowist]

thanks for the reply, the thing is its not even being picked up in "my computer"