Cant access External Hard drive after OS Re-install

Ive been running into a bunch of problems since I got my MAC. Dissapearing HD space being my main problem. I think Ive sorted that problem now after trying a some soloutions ending in reinstalliling the OS. but it seems the soloution caused a new problem because now I cant open my external Hard drive.

When verifying the disk in disk utility I get this message


Invalid Volume Header @ 0: unsupported format
Invalid Volume Header @ 319728958976: unsupported format
disk3s2 has CoreStorage features not supported by this fsck_cs version
Problems were found with the partition map which might prevent booting
Error: Storage system verify or repair failed.

Any advice?

Have you tried repairing the disk instead of just verifying it?

- Simon

Yes repairing the disk returns same message and fails.