Time Machine disk suddenly 'read only'

[catmother]

Help! After (successfully) burning a DVD with an iPhoto album containing 677 photos, I restarted our iMac (five yrs old, runs Snow Leopard, up to date). When I got back a while later, I saw “Time Machine could not complete the backup. Files can’t be copied onto the backup disk because it appears to be ‘read only.’” along with “Mac OS X can’t repair the disk ‘Time Machine HD. You can still open or copy files on the disk, but you can’t save changes to files on the disk. Back up the disk and reformat as soon as you can.” This seems very ominous, and I feel uneasy with the Mac Help “Repairing your backup disk” instructions to use Disk Utility > Repair since I can’t even find out **how** to back up the backup dish itself (which is a 500gb LaCie Neil Poulton USB 2.0 8MB). What shall I do, other than get some sleep and hope someone has answered me by morning?

Thanks in advance.

 

[iThinkergoiMac]

To backup the disk itself, you need to copy everything on that disk to another disk.

 

[spaceballl]

I'm having the issue where the disk is suddenly read-only too. does anyone know a good fix?