Which error its showing ?
U just check if the registry value has not been changed.

Hi members ..............................................................................................
Hi again. I have a 500g Iomega external hard drive that I use Time machine to back up both my iMac and my macbook. After today's update from Apple for iTunes, etc my backups stopped working. So, I rebooted the iMac and upon startup I was greeted with an error that basically said my external drive wasn't working (can't remember the exact words) So I ran the disk utility application and it said that it couldn't be repaired. So I reformatted the drive and started over. Restarted Time machine and everything seemed fine until the back stopped half way and restarted itself. At this point I gave up and zeroed out the hard drive and reformatted. Started Time machine again and it backed up the entire hard drive no problem. Then I set about trying to hook up the macbook to Time Machine, etc. I was having the normal trouble with this and at some point I rebooted the iMac. Then I got the same #$#$#%%# error about the external hard drive and I had to reformat again.
By regards
anglish0098
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