All the sudden not recognized by my Mac


I have a toshiba ext hard drive. I have data on it and I've never had a problem. Yesterday I moved my computer from one room to another. When I plugged the ext. back in, it doesn't show up on the desktop or in disc utility. My other two ext. drives show up like normal. The data shows up on my husbands and sons PCs but not on my mac... my husband formatted it to exFat but it still won't show up on my Mac... any suggestions on how to fix this?
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More about sudden recognized
  1. Does the drive show up in Disk Utility? If so, what is its status?
  2. it doesn't show up in Disk Utility... at all. Not on desktop nor disk utility. Worked fine yesterday, showed up on desktop with the other two ext drives...
  3. Have you tried different USB cables and/or USB ports? Also, verify that the external power adapter for the ext HDD is the proper one and it correctly attached.

    Lets rule out all the simple stuff first.
  4. I have tried different USB ports. The cable is not a standard USB on one end and a smaller version on the other. It has a USB on one end and a long thin connector to the hard drive. There is no external power adapter. It only has the USB cable. I can feel the disk running when it is plugged into my Mac. The indicator light is on too.
  5. Do you have Boot Camp set up on your Mac? If so, does the drive appear in Windows?

    When you moved the system, did you unmount the drive properly (if the drive was removed prior to powering down)?
  6. I never used the Boot Camp set. I'm fairly new to Mac. Before this iMac i had a Mac Mini. I didn't use the migration assistant either because I didn't have anything to migrate.

    When I moved the system I shut it down then unplugged everything. If I'm removing something (thumb drive or even iPod) I always eject first. This time since I had shut down the system I didn't eject the drives first.
  7. When you power down, you don't need to unmount/eject the drives.

    If you power the system on with the HDD attached -OR- if you attach the HDD after the system is fully booted up to OS X, does it make any difference? Do you get any notification from the Mac?
  8. Nope... after my husband formatted it to exFat and put everything back on the drive, I plugged it into the USB port. Nada... Then I shut down to see if the system found it. Again, no joy.
  9. When was exFAT applied, before or after this all happened?
  10. Also, what version of OS X are you using?
  11. I believe it was Fat32 initially. ExFat was done after the mac failed to show the drive. After I tried a few times (switching USB ports and such) we decided to try to format it to exfat (since hubby's pc doesn't to FAT32) and see if that would work. I'm beginning to think a new drive would be less painful.
  12. OS X is Lion 10.7.5
  13. Well, the good news is that your OS X version meets the minimum requirement to access exFAT drives (minimum of 10.6.5).

    As the drive was formatted recently, I assume there is nothing on it. Is that correct?

    If so, I would suggest going to a Windows box simply removing all partitions (pretty much wipe the drive) and then trying again with the Mac.

    Honestly, I am baffled by the Mac not detecting the drive being connected at all, but it is readable/useable by the other PCs. Especially since you said this happenss on all USB ports.

    BTW, do you have a powered USB hub attached to your Mac? If so, try connecting the drive to it. Just as a thought, you aren't plugging the HDD into the USB ports on your keyboard are you? If so, plug directly into the Mac.
  14. As for the formatted drive... there is data on it now. We fomatted it yesterday using exFAt. Then put all the data back on it.

    The USB hub is located on the back of my iMac. So I assume that is what you are asking as far as a "powered hub."

    I don't have any USB ports on my current keyboard. Tried that once with the old keyboard and a thumb drive... didn't like it.

    I appreciate all the help! I guess its just one of those things. :) I'll price some new hard drives... maybe even get myself a new Mac specific drive for Christmas.

    Thanks again for all your help and time!
  15. A powered USB hub is used to provide additional USB ports to systems. You can add 4-8 additional ports while only using one USB port on your computer. A powered HUB has its own power supply to provide power to devices.

    How many other USB devices are connected to your Mac? Have you tried with only the minimum stuff (keyboard, mouse, dreaded HDD in question) attached?
  16. Sorry it took me so long to reply... groceries... I don't know why people here think I should feed them. Sheesh. :)

    There are a total of three small externals (including the difficult one) and the occasional iPod or nook or thumb drive plugged in. The externals are always plugged in but the other stuff only gets plugged in when I need to add stuff to them.

    I did try just plugging in this toshiba only, unplugging all other devices. That didn't do it either. My husband said something about formatting this Toshiba in FAT32. I think he found a way to do it on his PC. We'll give that a try to see what we come up with.
  17. OK. I ask the power questions because if there was a lack of adequate power via the USB ports, this behavior is exactly what would happen.

    I think the format of the HDD is a bit of a red herring. Still worth checking out, but Disk Utility would still show a foreign disk as being present if it was physically attached and operating.

    The fact that it will work via the PCs would imply this (power issue) is possible.
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