Can't Mount 2 External Hard Drives at Once

I have two external hard hard drives, both Western Digital MyPassports, and when I connect both disks at the same time to my MBP, I encounter all sorts of problems. One will usually start making clicking noises and then randomly mount and unmount. This problem only occurs when I have both discs connected at the same time. If I connect each disk separately, they both function perfectly. Is there a reason why 2 external hard drives cannot be hooked up at the same time?

It sounds as though the two drives together are requesting more power than is available through the USB bus. I can't explain why this is manifested the way it is; it seems to me that if each drive works properly by itself when connected to one of the computer's USB ports, then both should operate properly together when both are connected to the computer's ports. Nevertheless, the disk behavior you describe is exactly what we saw for years and years with Powerbook G4s, whose USB ports were always notoriously underpowered. Buying an AC-powered USB hub and connecting one or both of the drives to that instead of directly to the computer should alleviate the problem.

Similar Messages

Can I mount external hard drive to Time Capsule and use it as external storage?

I have a 500GB external hard drive that I'd like to use on the Time Capsule as a hard drive to store mp3 and mp4 files. Can I attach it to the Time Capsule and use it like this? Or does it just give an additional 500GB worth of back ups from my iMac?

Can I attach it to the Time Capsule and use it like this?
Yes, if the drive has been formatted in Mac OS Extended (Journaled)...preferable....or FAT32. Access to the files will somewhat slower than if you had the drive attached directly to your computer.
Have you given some thought as to how you will keep this drive backed up?
Time Machine will not be able to back up the drive that is attached to the Time Capsule's USB port.
But, it would be able to back up the drive if you connected it directly to your Mac and the drive was formatted in Mac OS Extended (Journaled).

Can't mount external Hard drive and Can't change the ownership and permiss.

Hello everyone, got a problem and maybe someone here will know. Apple care can't help because this is due to an external piece. I have a hard drive external. I partitioned it into two hard drives. Long ago, I opened the information window for one of my partitioned drives. And changed the ownership and permission to "no access". I do this all the time to keep my files from being read if its not the administrator (me). Just recently I plugged in my hard drive (firewire and USB). Only one drive mounts on the desk top. I cannot see my other partitioned hard drive and I can' access it to change the ownership and permission with "apple key and I".. I can see a trace of the two partitioned hard drives when I use disc utility. But again it won't let me change the ownership so I can mount this again. How do I access my harddrive without refomatting? I have tried to mount this with both of my apple laptops..no luck yet. Please help, anyone.

Hi, Donnie. Welcome to the Discussions.
What part of "No Access" was unclear?
"No Access" means no access for anyone.
To fix this:
1. Launch Terminal, which resides in the Macintosh HD > Applications > Utilities folder.
2. At the Terminal prompt, type the following command:
sudo chmod a+rwx "/Volumes/partition_name"
where: partition_name is the name of the affected partition.
3. Press Return.
4. Type your Admin password when prompted, then press Return.
5. At the Terminal prompt, type exit and press Return.
6. Quit (Command-Q) Terminal.
7. Relaunch Finder: Press and hold the Option key, click and hold mouse button 1 on the Finder icon in the Dock, select "Relaunch" from the Finder icon's contextual menu.
You should then see the volume, or be able to use Disk Utility to Unmount it, then Mount it and see it.
Reset the permissions for Group and Other on the partition as desired. Do not change the permissions for Owner.
If you want a volume / partition unmounted at startup, see:
• this tip Mac OS X Hints, or...
• this tip on the OSX86 Project forums.
Good luck!
Dr. Smoke
Author: Troubleshooting Mac® OS X

Time Capsule can't backup external hard drives connected to it. Got that.

Hello Apple Support Communities! This is my first post. Hope this finds you all well My first year as an Apple user. I bought a 2-Tb TC and am running my first backup to my MacBook as I write this.
Problem statement: TC can't backup external hard drives connected directly to it, but the ones connected to the Macs that are connected wirelessly to it. Duly noted. However, the Spotlight will reindex the hard drives connected to the Mac and that will take hours; the whole backup will take days. Thus, excluding the hard drives at "System Preferences > Spotlight > Privacy tab" will probably help reduce the time of backup, or just ejecting them will do too. That itself has not proven effective coz it's still taking forever (50Gb in 2 days, still going).
Questions:
1) Do I wait until my first backup to my MacBook's internal hard drive is done before I connect my hard drives to my MacBook and attempt another backup? If yes, how do I go about the excessive time Spotlight reindexing takes if I intend to backup my hard drives connected to my MacBook?
2) Is there any other way of speeding up the first-time backup?
*Note: All versions of OS and firmwares are up-to-date. TC is connected to an external wireless router. TC is intended to be used as backup device and / or file server only.
P/S: Apologee if this has already been discussed before, thus, a link to previous discussion thread would highly be appreciated)
- Shook Hashem, Malaysia.

How do I backup the externel hard drives connected to my MB. I was under the impression that that has already been done, because I've read it somewhere in a discussion that said it's done automatically unless I exclude it from a backup, which I didn't. So it's supposed to backup the external hard drivestoo because I had them connected to my MB the entire time during the backups.
By default an external drive is excluded.. the list is odd.. if I plug a drive into the mac.. it immediately is listed as excluded.
This is not the list of included.. this is the list of excluded.. remove it from the excluded list to include it.
It is kind of reverse polish notation in backups.
If I want to enter the Time Machine, should I enter it with the TM turned on or off?
Not sure what the question means. If you use the star wars display and want to recover files then use TM off.. but read up pondini.. how to do restore etc.
http://pondini.org/TM/FAQ.html
15A in particular on the how to use TM.
When do I uplug the ethernet and use the wireless connection instead?
Once you have finished the main backup you can go back to wireless. The incremental backups are mostly very small.

Can not fine external hard drive for time machine sence lion was installed

I can not fine external hard drive for time machine sence lion was installed, it don't reconise it at all.

I have a Mac Mini (late 2009) and I have an iomega 1TB external hard drive connected to my mini via firewire and usb (usb allows me to use the usb ports on the external 1TB drive to daisy chain other devices). Since I installed Lion, my Time Machine and this 1TB drive (and its partitions) is finicky. Sometimes it is mounted and sometimes it is not. This issue has only surfaced post Snow Leopard and in the Lion era. I am not the first to say this but the whole reason I went Mac was b/c of Vista. I am beginning to think that Lion is the new Vista. Sorry for the latter, just venting... b/c this ain't the first issue with Lion.

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

Everything looks clean, as far as I can tell.
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

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)

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

Can not get external hard drives to connect to my computer 17" Mac book Pro 10.7.5

can not get external hard drives to connect to my computer I am using a 17" Mac book Pro 10.7.5.
I have 2 iomegas and 1 LaCie. Changed cables. I can feel the external hard drives running and
I can hear them running but I can not get them on the computer any more. They did work at one time.
Can any one PLEASE help?

Nothing appear on my desktop.
I did Repair and Verify the HDDs in Disk Utility>First Aid from the
Utilites App about a dozen times ans they all said everything was good
except for the last time there were erors found and I ran the
Disk Utility from the Start Up Disk and the repairs were made and everything
was subposed to te good and still Nothing on the desk top.
Ginger

Hello, I have two questions on time capsule I can only have it on my external hd files and free up my internal memory to my mac I can use an external hard drive, in my case a lacie rugged as shared memory for my two computers

Hello, I have two questions on time capsule I can only have it on my external hd files and free up my internal memory to my mac I can use an external hard drive, in my case a lacie rugged as shared memory for my two computers

I have a mackbook pro and an iMac if I buy a time capsule 2tb airport, I can use it with time machine and what would be the best way to use it.
There is no particular setup required for TM.. both computers will create their own backup sparsebundle which is like a virtual disk.. Pondini explains the whole thing if you read the reference I gave you.
and how to use time capsule airport whit other external hd to use my old lacie airport with the new time capsule
Up to you.. you can plug the external drive into the TC and enjoy really slow file transfers or you can plug it into your computer and use it as external drive.. which is faster than the TC.. and TM can include it in the backup.
Again everything is explained in the reference.. you are not reading it.

Can you use external hard drives with the HP Omni 10 5600US

Since this a Windows tablet, can you use external hard drives with the HP Omni 10 5600US?
I know there is a micro-sd reader for additional storage but can you use the usb for external hard drives like a regular pc?
I tried looking at the spec's for this tablet and it said the usb port was host only. I'm not sure what that means exactly.

Yes you can. You'll need to purchase a USB OTG (on-the-go) cable. I recommend using a drive that has its own power supply but I've successfully used small USB powered drives also.

Is there a way I can use my external hard drive without the files being transferred on to my computer? as like like my iTunes music being on my hard drive without them being copied onto my computers hard drive ?

is there a way I can use my external hard drive without the files being transferred on to my computer? as like like my iTunes music being on my hard drive without them being copied onto my computers hard drive ? because i dont have that much memory and i wanted my external hard drive to be the source for my music files and not my computer.

Many users keep their iTunes libraries on external drives. You just have to remember to connect and power up the drive before launching iTunes.
iTunes for Mac: Moving your iTunes Media folder:
http://support.apple.com/kb/HT1449

Can iTunes utilize more than one external hard drive at once?

A couple of years ago we had the bright idea to get a mac mini with an external hard drive and load it up with movies and such, so when we wanted to watch a tv show or movie, we could just scroll through the titles and pick without having to deal with the actual DVD (the mini is hooked up to a flatscreen tv). Needless to say, this monster has grown to epic proportions and we have since upgraded to 2 external hard drives (totaling 5 TB), and we now use another program that utilizes both hard drives without problem.
The issue I am having is that we bought an AppleTV tonight, and have not had any problems getting iTunes to see the movies in the "Movies" External HD, but the tv shows are on another External HD and they take up a little more than 345 GB of space. I kinda liked having the two drives separate, but was wondering if there was a way to make the mini think these two drives were just one? I know it is a strange question, but I can't think of a solution at this point.
Is there a way to tell iTunes to look in two locations for content?

I am wondering if this set-up will work if I daisy chain the external drives. My iTunes library is stored on a 1.5 TB external drive. I have about 350 GB of storage left. I have been trying to find a way to add a drive instead of replacing the drive with a larger drive. If I can daisy chain, this will allow me to add storage without losing another firewire port. I just want to make sure this all works before I attempt any changes. Thank you.

I had to reformat my computer and put my Itunes on an external hard drive. Once I fixed my computer and put Itunes back I can't itunes to open on my PC. I see it but it appears locked now.

I reformed my PC and placed my Itunes on a external hard drive. I have moved them back to the PC but can not open. How are i get my Itunes working I can see them in my files but they are locked.

I'm sure when it was taken to reformat, he just put everything from my computer onto the external. I know he did't save them to any back up disc's. When he moved everything back is when I lost my Itunes library and it only shows as that XML. I do have an old back up I can restore most.
Any way to import from my touch what is on it, I have not connected it to my PC since.
I did get all my music purchased on, but under purchased I can't find my movies.
Thank you!!

Mac can't find external hard drive

Hi,
I've had an external hard drive for my mac now for over a year. It's been working wonderfully, however, recently the hard drive can no longer be recognized by my mac. It doesn't come up in the Disky Utility and it doesn't come up in System Profiler. Naturally, there's a lot of stuff on there I want to keep. How can I get this thing mounted again?

Our company's system admin made me aware of Scannerz, which is a test tool. Their web site in the how to and downloads section has a lot of info on that type of stuff. The link is:
http://scsc-online.com
I saw that happen once when the drive became corrupt and Disk Utility wouldn't see the drive. There's a command line way to use Disk Utility and the drive doesn't show up with a name but with a disk id like /dev/disk023s23 (something like that...that's an example).
Also, check your drive cable. It might have gone bad.

Mount external hard drive

My Mac crashed and when I restarted it I can only see 1 partion of my external hard drive.
I have tried going to disk utility to load the partion but it wont load
Please can anyone advise how to mount an unmounted drive?
This is what is in the log
Starting Restore…
Starting Restore…
An error (19) occurred while copying.
Mount of “Mac” succeeded
Mount of “Mac” succeeded
Starting Restore…
Starting Restore…
An error (2) occurred while copying.
Thanks for your help

If this is not the drive you are booting from, you should be able to run Disk Utility's "Repair" function without booting from the CD. Otherwise, boot from the Installer CD, but do not install. Instead, choose Disk Utility from the Installer menu.
Since you booted from another Drive or the Installer CD, when you select the drive, you will be able to use the "Repair" button. Run it repeatedly until there is no change between successive passes, then (if Mac OS X is present on it) run "Repair Permissions" once. Report any unresolved errors from "Repair" here. "Repair Permissions" chatters on forever about nothing, and its messages can generally be disregarded.
Error (2) is a Bus error. It is a very serious error, which should have crashed your Mac. Error (-2) is an invalid queue element, which can be caused by directory damage.
Error (19) can be caused by a damaged System Folder. Error (-19) is a color-manager error.

Can't Mount 2 External Hard Drives at Once

Similar Messages

Maybe you are looking for