DISK UNIX ERROR

Hi there

I keep getting strange errors in the past few days - DISK_UNIX_ERROR. maybe there is something to do with the media drive? its not the fastest but it works ok (I worked with it few time before and no error)-Lacie firewire800

After i open the project, I get the error and then all the clips and seq are offline.

I tried to open a new project, and another error occurred every time i tried to save the project.

is there any way to fix it?

I'm working with the MC 7, Imac OSX 10.7.5

Thanx

Shira