Level 1

103 points

Not recognizing external hard drive

I have a 1 terabyte seagate external hard drive that I used to back up my PCs and tried to connect it to my Macbook Pro to transfer the files over from my old computers, but the Mac won't recognize the external hard drive at all. Any suggestions?

Macbook Pro 15" 2.66 ghz, Mac OS X (10.6.4)

Posted on Sep 5, 2010 1:58 PM

187 replies

Weeblerock Author

Level 1

103 points

Sep 5, 2010 9:01 PM in response to JasonFear

It wasn't being recognized in Finder or in System Profile. I suspect that the drive has been formatted using the NTSF system, but I haven't actually double checked that. Does anyone have a recommended program for reading/writing NTSF on a mac?

JasonFear

Level 5

4,965 points

Sep 6, 2010 2:15 AM in response to Weeblerock

Weeblerock wrote:
It wasn't being recognized in Finder or in System Profile.

Hi Weeblerock,

Are you sure it's not being recognized in System Profiler? Because that's a whole other bag of issues. By System Profiler I'm referring if you go Apple Logo > About This Mac > More Info and then select the bus that the drive is connected via to your computer. Which is most likely USB.

Disk Utility, an application within the Utilities folder is something completely different. If it sees it there and it's not a mount point then it's an NTFS / OS X file format issue. Macs can read from NTFS volumes but I'm not aware of a method to write to an NTFS volume.

Weeblerock Author

Level 1

103 points

Sep 6, 2010 3:41 PM in response to JasonFear

That's what I thought. And it definitely doesn't show up in System Profiler or Disk Utility. But the drive detects the connection at least (and lights up), and the USB port works for other devices like my printer.

JasonFear

Level 5

4,965 points

Sep 6, 2010 4:57 PM in response to Weeblerock

Hi Weeblerock,

That's interesting. The fact that it's not seeing the drive even in System Profiler is not a good sign, as the drive isn't even being seen at the bus (I/O) level. Is it a bus powered drive or does it draw power from the wall as well?

The fact that the drive isn't even being seen via System Profiler tells me that it's not a partition/formatting issue but more of a hardware compatibility issue. Any other external HDs to test against?

Sep 6, 2010 8:56 PM in response to Weeblerock

Having same problem - I have tried three hard drives and three cords. Recently installed an update that Apple pushed down, could this have something to do with it?

Weeblerock Author

Level 1

103 points

Sep 7, 2010 5:09 AM in response to JasonFear

The drive also draws power from the wall. I don't have any other external drives to test it with but it does work for my printer when I connect via USB. Also, I'm relatively certain that my computer is up to date with all Apple updates.

ahs2010

Level 1

0 points

Sep 8, 2010 3:30 PM in response to Weeblerock

I am having the same issue. Seagate replaced my 500gb drive and it is still not recognized by my Macbook Pro. Can you guys let us know if there is an issue with macbook's compatibility with the Seagate Hard drives.

Ganamex

Level 1

5 points

Sep 21, 2010 5:50 PM in response to Weeblerock

Jumping into this thread to say I've run into the same problem--my WD Elements 1TB drive works fine on Windows computers (I've tried a few), but my Macbook Pro won't even pick it up at the I/O level. I'd reformat the drive if I could only get my Mac to recognize that the darn thing exists, heh. Any suggestions appreciated...

Oct 14, 2010 5:49 AM in response to Ganamex

I have the same problem. I have been using an external hard drive for a few months now and all of a sudden my Macbook has stopped recognizing the drive when I plug it in as I always correctly had done. It says TimeMachine is Delayed. My last back up was Oct 2, 2010. I have tried restarting my computer with the drive attached and with it not attached. Still does not recognize it. When I say recognize I mean it does not show up on the desktop and the time machine application cannot see any attached drives.
Any help is appreciated.
Thank you

Oct 17, 2010 12:11 AM in response to CbuscCycler

I have the same problem where the system has suddenly decided to stop recognising my USB drive. until recently all my backups were on this drive, now it cannot find it???
What is going on? was it the latest software update??
How do I get it back?
Please help

Oct 17, 2010 4:57 AM in response to CbuscCycler

Just thought I let you know, i reformatted (deleted ) the drive sacrificing previous backups and immediately the drive was recognised by my system and the icon appeared on the desktop.
I believe that the last upgrade to the mac software is the culprit that made the drive disappear until reformatted.
It may be a price to pay to reformat but at least you get the drive back and can do a new backup.
Hope this helps
Co

Message was edited by: Co de Kleuver

Nov 4, 2010 12:20 PM in response to Weeblerock

QUESTION

i too have a wd external hard drive.
i lucked out and my mac recognized it so i got my files off. but now the mac is not finding now.
so how do i reformat it to mac?
the HS still comes up on my windows computer so....

can i reformat to mac while i have it plugged up to a PC?

thanks so much.

Nov 4, 2010 12:23 PM in response to Co de Kleuver

"Just thought I let you know, i reformatted (deleted ) the drive sacrificing previous backups and immediately the drive was recognised by my system and the icon appeared on the desktop."

system being mac OS?
are you saying if you wipe the WD mac will recognize it?

Dec 3, 2010 7:45 AM in response to CbuscCycler

I have had the same exact experience. Time Machine suddenly stopped working, only to give me the "delayed" error. And my machine no longer recognized the external hard drive.

Jessek

Level 1

15 points

Feb 2, 2011 8:41 PM in response to kreesetaylor

I am having this same problem. I have a USB external drive and a Firewire 800 drive that I was backing up to using Time Machine and suddenly Time Machine just froze up. Then when I restarted the machine just gave me a grey screen and wouldn't boot until I disconnected the drives.

Now the drives won't show up in the finder. I can see them attached using system profiler but I can't access them. This is really frustrating.

Anyone have any solutions?

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Not recognizing external hard drive