Hey, I'm confused with what's happening with my backups. I had me external drive connect to my iMac for a year now (using Time Machine). Yesterday I put my HDD on my airport extreme so other people on my network could access it. Turns out no one want's to access it and so I put it back on my iMac via USB so it's faster to access for me. Now when I point time machine to the same HDD it want's to make new backups of everything and can't because I only have 40 Gb left. The existing Backups.backupdb is still there. Any help?