problem solved for now
Hi all,
I had this problem happen to me a couple of days ago. Not only was my Lacie 1TB Rugged XL Hard Drive being reported by Time Machine as 'Read-Only', the icon was not even showing on the desktop once the drive was connected and switched on, and also the drive wasn't showing as an available disk in the Time Machine Prefs.
I could however see the disk in Disk Utility, and after seeing that my symptoms were exactly as others had described in this thread - I clicked Veirfy Disk.
DU informed me the disk was in need of repair, so I went ahead and clicked repair disk from the menu. After a few minutes, I was again informed that the disk could not be repaired and that I should back-up my files (how ironic) and erase the disk.
By this stage however, the disk had then reappeared on my desktop. I went back into the Time Machine Prefs, found the disk available once more, and at the time of writing I have successfully completed a back-up of 6.5GB of data.
Strange situation that I can't trace back to a particular incident, either with MacOSX or the drive. Let's just hope it stays this way. Will report back if it happens again.
Cheers