# External Hard Drive won't mount



## polostar (Mar 11, 2013)

I have a 1TB western digital external hard drive that isn't mounting. When I plug it in, the power light comes on and I can hear it spinning, but it won't mount. I've tried switching USB connectors. It's connected directly into the computer and not a USB hub. I've reset the PRAM, run disk first aid, which said the disk was fine, and it still won't mount. As mentioned previously, it will show up in disk utility. I only use it as a backup with Time Machine. Any ideas of what to do next?


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## sinclair_tm (Mar 11, 2005)

When it shows up in Disk Utility, does it just show the hard drive, or does it also show the disk volume as well. And if you click on the volume, can you click on the Mount button at the top of the window?


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## polostar (Mar 11, 2013)

It shows the disk volume. I've clicked on it, and then clicked on mount, but it just says that the volume is unmountable and to run disk first aid.


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## sinclair_tm (Mar 11, 2005)

What happens when you run Disk First Aid?


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## polostar (Mar 11, 2013)

It says that Disk First Aid couldn't detect any problems.


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## Tomshawk (Jan 23, 2013)

In disk management, you say it says it is there but unmountable

What does it say as Volume type, Does it say it is a foreign disk?


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## johnny_stocazz (Mar 13, 2013)

When my gf's drive acted like that stopped working at all after a week.


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## sinclair_tm (Mar 11, 2005)

johnny_stocazz said:


> When my gf's drive acted like that stopped working at all after a week.


And that adds to the conversation how?

Like Tom said, what format does it say the disk is? Click on the drive, and it's volume and see what is listed at the bottom of the window for size, format, and status.


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## polostar (Mar 11, 2013)

Here's some screen shots. I figured it would be easier than typing everything.


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## polostar (Mar 11, 2013)

Here's the log file from disk first aid.

2013-03-10 20:54:47 -0600: Disk Utility started.

2013-03-10 20:59:35 -0600: 
Name : Apple Backup
Type : Partition

Disk Identifier : disk1s1
Mount Point : Not mounted
File System : Mac OS Extended (Journaled)
Connection Bus : USB
Device Tree : IODeviceTree:/[email protected]/[email protected],1
Writable : Yes
Universal Unique Identifier : F9644263-12AD-347A-B880-834CAC76FFAC
Capacity : 1 TB (1,000,204,884,992 Bytes)
Owners Enabled : No
Can Turn Owners Off : Yes
Can Be Formatted : Yes
Bootable : Yes
Supports Journaling : Yes
Journaled : No
Disk Number : 1
Partition Number : 1


**********
2013-03-13 18:40:15 -0600: Disk Utility started.

2013-03-13 18:50:20 -0600: Verify and Repair volume “Apple Backup”
2013-03-13 18:50:20 -0600: Starting repair tool: 
2013-03-13 18:50:28 -0600: Checking file system2013-03-13 18:50:28 -0600: Checking Journaled HFS Plus volume.
2013-03-13 18:50:28 -0600: Detected a case-sensitive volume.
2013-03-13 18:50:28 -0600: Checking extents overflow file.
2013-03-13 18:50:29 -0600: Checking catalog file.
2013-03-13 18:51:47 -0600: Checking multi-linked files.
2013-03-13 18:52:07 -0600: Checking catalog hierarchy.
2013-03-13 18:53:59 -0600: Checking extended attributes file.
2013-03-13 18:54:38 -0600: Checking multi-linked directories.
2013-03-13 18:57:56 -0600: Checking volume bitmap.
2013-03-13 18:57:58 -0600: Checking volume information.
2013-03-13 18:57:58 -0600: The volume Apple Backup appears to be OK.
2013-03-13 18:57:58 -0600: Volume repair complete.2013-03-13 18:57:58 -0600: Updating boot support partitions for the volume as required.2013-03-13 18:57:58 -0600: Repair tool completed: 
2013-03-13 18:57:58 -0600: 
2013-03-13 18:57:58 -0600:


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## sinclair_tm (Mar 11, 2005)

I see the dive is listed as MBR instead of GUID. Not sure of that makes a difference, but it might if it's bad. You said you use it for Time Machine, so, do you care if you lose any data that is currently on the drive, AKA, do you need those backups? If not, I'd say click on the drive, make sure it's set up as GUID (which will make it Mac only) and click the erase button and see if it comes back. If you need to keep the data, then do you have another Mac you can try it on?


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