Finder can't see external hard drive

Question

Finder can't see external hard drive

All of a sudden, my PowerBook G4 can no longer see my external hard drive (Maxtor 160 GB drive). The drive doesn't appear in the Finder, and it doesn't mount on the desktop. Thus, I have no way of accessing the files on my external hard drive.

I can see the external hard drive when I launch Disk Utility (and also when I launch TechTool Pro), so I know the hard drive and the USB connections are working.

Can someone please help on this?? I've tried unplugging everything and rebooting with no results. Thank you.

PowerBook G4 Titanium 1ghz processor Mac OS X (10.4.2)

Posted on Mar 29, 2007 12:56 PM

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Answer 1

Best reply

Francine Schwieder

Level 6

19,052 points

Mar 29, 2007 2:09 PM in response to Robert Montgomery1

If you use the Finder's Go menu and select the Go to Folder option, then type the path to something on the drive, does Finder open a window to the folder? Thus if your drive is named "External" and has a folder named "MyStuff" you would type this in the Go to Folder dialog box:

/Volumes/External/MyStuff

and click the Go button. If this works, then your drive has had the invisible bit set. See this thread:

http://discussions.apple.com/thread.jspa?threadID=865694&tstart=0

The Applescript for drives will fix it, scroll down a bit to see it.
Francine

Francine
Schwieder

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Answer 2

Mar 29, 2007 2:52 PM in response to Francine Schwieder

Hi Francine - I was unable to access my folders via the Go to Folder command (I received an error message of "The folder cannot be found"). Just to confirm: should I still proceed to the thread you referenced in your post and implement the Applescript (I ask because in your reply you said " If this works, then..."?

Thank you in advance for any insight,
Bob

PowerBook G4 Titanium 1ghz processor Mac OS X (10.4.2)

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Answer 3

Mar 29, 2007 3:10 PM in response to Robert Montgomery1

Just to make sure you typed the right info into the dialog box:

I have a drive named OXey, with a folder named Documents at its "root" level (the level you see when you double click the OXey icon). If that drive simply went invisible, typing in this:

/Volumes/OXey/Documents

would open the Documents folder. If you are sure you spelled the name of your drive, and a folder accessible on its root level, correctly (and capitalization matters), but still can't access the drive, then the problem is not that it is invisible, but something else.

When you say you can see it in Disk Utility, just exactly what are you seeing? When you select it is the Mount button available? Finally, have you ever used Terminal? There are some commands in Terminal that may help sort it out.
Francine

Francine
Schwieder

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Answer 4

Mar 29, 2007 5:55 PM in response to Francine Schwieder

Yep, I typed everything in correctly. Still no go (as it were).

I can see my external hard drive listed in the left-hand pane of Disk Utility, along with my PowerBook's internal drive. When I select the external hard drive, the mount button is available. Here's something curious, though: when I select the external hard drive and click mount, the icon for the external hard drive transforms from a USB hard drive icon to what looks like a Word doc icon. Not sure what that's all about... Anyway, even after I mount it, the Finder still can't see it and Disk Utility can't see how much space has been used or is available, etc.

Any ideas?? I'm not very familiar with Terminal, but am willing to give it a shot.

Thank you,
Bob

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Answer 5

Mar 30, 2007 12:44 AM in response to Robert Montgomery1

Have you tried selecting the drive in Disk Utility and then tried to use the First Aid option of Repair Disk?

And here's some Terminal things to try:

Launch Terminal from your Utilities folder. When it is up and running type this (or copy and paste):

diskutil list

Hit the Return key to execute the command. It will print out information about everything it can see. Here's a sample from my Terminal:

-bash:~francine$ diskutil list
/dev/disk0
#: type name size identifier
0: Apple partitionscheme *57.3 GB disk0
1: Apple partitionmap 31.5 KB disk0s1
2: Apple_Driver43 28.0 KB disk0s2
3: Apple_Driver43 28.0 KB disk0s3
4: Apple DriverATA 28.0 KB disk0s4
5: Apple DriverATA 28.0 KB disk0s5
6: Apple_FWDriver 256.0 KB disk0s6
7: Apple DriverIOKit 256.0 KB disk0s7
8: Apple_Patches 256.0 KB disk0s8
9: Apple_HFS TigerBU 57.1 GB disk0s10
/dev/disk1 (and so on, I'll leave out the details on two other mounted drives)
....
/dev/disk3
#: type name size identifier
0: Apple partitionscheme *125.0 MB disk3
1: Apple partitionmap 31.5 KB disk3s1
2: Apple_HFS Keydrive 125.0 MB disk3s2

The last item is a currently unmounted USB drive. To mount it using the Terminal you use the diskutil mountDisk command, identifying the the drive with the information you get from the list command. Thus to mount the USB Keydrive I typed this and hit Return:

-bash:~francine$ diskutil mountDisk /dev/disk3

To verify that it mounted I used the list command:

ls -al /Volumes

Hit return, and got a list of all mounted drives/partitions, including the Keydrive. It looked like this:

-bash:~francine$ ls -al /Volumes
total 24
drwxrwxrwt 10 root admin 340 Mar 30 00:31 .
drwxrwxr-t 41 root admin 1496 Mar 29 23:10 ..
-rw-rw-rw- 1 francine admin 6148 Mar 29 11:30 .DS_Store
drwxr-xr-x 27 francine francine 1020 Mar 27 21:25 Data
drwxr-xr-x 6 francine francine 306 Mar 24 16:24 Keydrive
lrwxr-xr-x 1 root admin 1 Mar 29 23:10 NoobiX -> /
drwxr-xr-x 52 francine francine 1870 Mar 8 00:11 OXey
drwxrwxr-t 46 root admin 1666 Mar 28 22:14 Panther
drwxr-xr-x 21 francine francine 816 Feb 18 02:01 TigerBU

If the drive is messed up in some way so that the Terminal seems to sit and do nothing after you hit the Return key (it does take a few seconds to do its thing and report to the screen), you can hit the Control and C keys simultaneously to abort the command.
Francine

Francine
Schwieder

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Answer 6

Mar 30, 2007 12:46 AM in response to Francine Schwieder

Francince, I've determined that the problem must have something to do with permissions or access levels or something, because when I log into my PowerBook using the guest login (instead of my usual login account), the Finder can see the hard drive.

Any idea where to go from here? I have Fast User Switching, so I can switch back and forth from the Guest Account (where I can see the hard drive), to my main account (where I can't see the hard drive). What do I need to do to ensure that I can see the hard drive when I'm logged into my main account?

Many thanks in advance...

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Answer 7

Mar 30, 2007 10:40 AM in response to Robert Montgomery1

By the way, here are my test results from running Disk Utility and Tech Tool Pro. Everything looks clean, I think?

Disk Utility says:

"The volume External Hard Drive appears to be OK.
Mounting Disk.
1 HFS volume checked.
No repairs were necessary."

TechTool Pro volumes test says:

Volume Structures

Thursday, March 29, 2007 6:24:26 PM US/Pacific
Passed

Volume: External Hard Drive
Mount Point: /dev/disk1s3
Format: HFS+ (Mac OS Extended)
Journaling: Enabled
Case-sensitive: No
Created: 03/26/07 01:26:09 AM
Modified: 03/26/07 01:26:09 AM
Capacity: 152.54 GB
Used: 49.81 GB
Available: 102.74 GB
Files: 86,074
Folders: 16,342
Writable: Yes
Ejectable: No
Removable: No

There are a variety of invisible files, settings, and parameters that the Macintosh file system uses to locate files, free disk space, and for other maintenance and management routines. Damage to these critical data structures can result in lost or damaged files and may even necessitate a complete reformat of the volume.

Precheck Structures
This test checks the readability of the various volume structures.
Boot Blocks
This test validates the Boot Blocks portion of the volume. This block of data is created when the volume is blessed.
Boot Blocks <Passed>

Master Directory Block
This test validates the Master Directory Block portion of the volume. This block of data is created when the volume is created and contains important data about the rest of the volume.
Master Directory Block <Passed>

Volume Header
This test validates the Volume Header portion of the volume. This block of data is created when the volume is created and contains important data about the rest of the volume like number of files and folders, and the amount of free space available on the volume.
Volume Header <Passed>

Allocation File (Bitmap)
This test checks the Allocation file. This file indicates which blocks are allocated for use and which blocks are free.
Allocation File (Bitmap) <Passed>

Extents File (B-Tree)
This test checks the Extents file. This file contains the extent data for the entire volume. Extents are the separate components of a fragmented file.
Extents File (B-Tree) <Passed>

Catalog File (B-Tree)
This test checks the Catalog file. This file keeps track of all the files and folders on the volume.
Catalog File (B-Tree) <Passed>

Attributes File
This test checks the Attributes file. This file tracks all of the attributes of each file and folder on a volume. Some attributes include whether the file is locked or not and the last time the volume was backed up.
Attributes File <Passed>

Startup File
This test checks the Startup file. The parameters within this file contain the information used by the computer ROM to determine what program will boot the computer as well as other system-specific aspects.
Startup File <Not Present>

Completed
Passed

Tech Tool Pro File structure says:

File Structure

Thursday, March 29, 2007 6:30:25 PM US/Pacific
Passed

Volume: External Hard Drive
Mount Point: /dev/disk1s3
Format: HFS+ (Mac OS Extended)
Journaling: Enabled
Case-sensitive: No
Created: 03/26/07 01:26:09 AM
Modified: 03/26/07 01:26:09 AM
Capacity: 152.54 GB
Used: 49.81 GB
Available: 102.74 GB
Files: 86,074
Folders: 16,342
Writable: Yes
Ejectable: No
Removable: No

This test checks for file resource corruption on the volume 'External Hard Drive'. If any damaged files are found, TechTool Pro will let you know which files have corrupted resources.

Analyzing File Structures

Passed

I'll let you know if Tech Tool Pro's surface scan of the drive turns anything up (it's running right now - takes several hours to run), but hopefulyl this provides a good starting point into painting a picture of my system...

Thx - Bob

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Answer 8

Mar 30, 2007 11:58 AM in response to Robert Montgomery1

The information on the drive itself looks like it is fine, and the fact that it actually is mounted and can seen in another user account confirms that the drive itself is fine, it is just access from your regular account that is somehow troubled.

In the account that can see the drive, select the drive and do a GetInfo on it. Down at the bottom of the GetInfo window there is a section on Ownership&Permissions, expand this section fully so you see all the options (click on the wee little disclosure triangle). There is also a line at the very bottom with a check box to "Ignore ownership on this volume." If you do not use the drive as a bootable system clone you can simply check the box and all users should be able to access the drive.

The correct details for drives that everyone can access:

Owner: system
Access: Read&Write
Group: admin
Access: Read&Write
Others: Read only

And the very top entry for "You can" should be "Read&Write" for every account you are logged into.

Interestingly, my USB Keydrive, when I look at Ownership&Permissions from my account (it has the "Ignore ownership" box checked), shows Owner as me, group as me, others as Read only. When I am in my test account, it shows those things as the above (system and admin).

You can change the settings in Details by clicking the little lock icon next to the Owner's name, give your password, and then make the changes.
Francine

Francine
Schwieder

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Answer 9

Mar 31, 2007 5:10 PM in response to Francine Schwieder

I started to change the access permissions, but Fast User switched back to my main account to research something on the Internet before finishing up. I must have left the access permissions in some weird, unfinished limbo state because now I can't see the hard drive from my main account or my guest account! I just created two new accounts (one admin, one standard) and they can't see the hard drive either.

Please, is there any way to make my hard drive become visible again, or to reset the access permissions?

Thx - Bob

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Answer 10

Apr 1, 2007 9:19 AM in response to Robert Montgomery1

Robert

Francine suggested you try these commands in Terminal:

diskutil list

and

ls -al /Volumes

but so far you haven't done so. Please do that and copy and paste the Terminal output here.

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Answer 11

Apr 1, 2007 9:43 AM in response to Michael Conniff

Here's what diskutil came up with:

Last login: Sun Apr 1 09:31:08 on ttyp1
Welcome to Darwin!
[Bob-Montgomerys-Computer:~] bobmontg% diskutil list
/dev/disk0
#: type name size identifier
0: Apple partitionscheme *55.9 GB disk0
1: Apple partitionmap 31.5 KB disk0s1
2: Apple DriverATA 32.0 KB disk0s2
3: Apple DriverATA 32.0 KB disk0s3
4: Apple_Patches 256.0 KB disk0s4
5: Apple_HFS Macintosh HD 50.9 GB disk0s5
6: Apple_HFS eDrive 5.0 GB disk0s6
/dev/disk1
#: type name size identifier
0: Apple partitionscheme *152.7 GB disk1
1: Apple partitionmap 31.5 KB disk1s1
2: Apple_HFS External Hard Drive 152.5 GB disk1s3
[Bob-Montgomerys-Computer:~] bobmontg%

And here's what ls -al /Volumes came up with:

[Bob-Montgomerys-Computer:~] bobmontg% ls -al /Volumes
total 40
drwxrwxrwt 8 root admin 272 Apr 1 09:31 .
drwxrwxr-t 31 root admin 1156 Apr 1 09:11 ..
-rwxrwxrwx 1 bobmontg wheel 6148 Mar 15 2005 .DS_Store
-rwxrwxrwx 1 bobmontg staff 82 Mar 8 19:18 ._Bob Montgom
-rwxrwxrwx 1 bobmontg staff 82 Mar 8 19:17 ._IPOD
d---r-xr-x 13 bobmontg staff 544 Mar 29 18:35 External Hard Drive
lrwxr-xr-x 1 root admin 1 Apr 1 09:11 Macintosh HD -> /
drwxr-xr-x 3 bobmontg admin 102 Dec 3 2005 jed.is-a-geek.com
[Bob-Montgomerys-Computer:~] bobmontg%

Can anyone help me out here? I think I somehow screwed up my access/permission levels. thank you!!!

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Answer 12

Apr 1, 2007 11:22 AM in response to Robert Montgomery1

I begged Michael for help, as he is my personal all-time favorite Mac UNIX guru, and it looks like we really need his assistance. It looks to me like your external drive is just fine and is mounting. However, you have somehow managed to deny the owner (yourself) read, write and execute privileges to the drive. Thus you can't see it. Michael knows what Terminal command you need to make these correct.
Francine

Francine
Schwieder

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Answer 13

Apr 1, 2007 1:38 PM in response to Francine Schwieder

Thank you for all your help thus far, Francine - I really appreciate it. Hopefully Michael can set me straight so that I can access the files on my hard drive again!

-Bob

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Answer 14

Apr 1, 2007 2:32 PM in response to Robert Montgomery1

Hi again Robert

I didn't expect to be away for quite so long!

As Francine said, you've somehow managed to remove all permissions for yourself from that volume, but it is an easy fix. I'm not sure why you are unable to do it with Finder, but anyway, copy and paste the following into the Terminal window followed by a return:

chmod u+rwx /Volumes/External\ Hard\ Drive

Hopefully any permissions on lower level folders in the drive will not have been affected, but if they are, Finder's "Get Info" should allow you to adjust them.

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Answer 15

Apr 1, 2007 2:51 PM in response to Michael Conniff

Problem solved!!! Thank you so, so, so much, Francine and Michael.

Best regards,
Bob

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