External volume is suddenly read only

Mountain Lion on 2009 Macbook Pro. I have a Drobo S with three volumes. One of the volumes has become read-only. I cannot change this in the Finder. This happened with a different volume a couple of days ago. This never happened before I upgraded to Mountain Lion three days ago. Restarting has fixed the problem both times. but it is a pain and can be a big problem if it returns in the middle of a write or large backup.
Here is a screen grab of the volume info in the Finder.
What is happening and how do I prevent this?

Usually that means the drive is malfunctioning. Back up all data on it, if you haven't already done so, then erase and restore. If you ever have another problem with the drive, replace it.

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External drive is suddenly read-only, yet is formatted for Mac

I've had a 1TB external hard drive for the last year and never had a problem with it until now. Suddenly, it is showing as read-only, however, it's formatted for Mac. How am I able to fix this? Do I have to re-format it?

Usually that means the drive is malfunctioning. Back up all data on it, if you haven't already done so, then erase and restore. If you ever have another problem with the drive, replace it.

External Hard Drive suddenly "Read Only"

I have been successfully using an external drive (WD Passport, Mac OS Extended) as my "Home" folder for about a year. Yesterday it started acting funny, not letting me open applications then my iPhoto library began running very slow. So I relaunched iPhoto and it would not let me use my iPhoto library saying it was on a locked drive.
I rebooted the computer and than I was greeted with an error window saying the drive was damaged but I could still access my data. I tried to run repair tools (Disk Utility, Disk Tools Pro and Techtool) but it couldn't repair anything because the disk somehow became read only.
When I did a "Get Info" all my users had "Read & Write" privileges, except "Everyone" was "Read Only".
I clicked on the padlock to make changes but it was grayed out.
Do I have to do a full Back up and reformat? Does anyone know why this would happen and how to fix it and avoid it in the future? Is there a terminal command or a different way to change access to my drive?
FYI - also the "Ignore ownership..." box on the drive is unchecked.
Any help would be appreciated.
Thanks!!
Message was edited by: Skip

Mickey and Skip,
I get very suspicious about "strange happenings" like this.
As an old hand in computing, I suspect that these are symptoms of imminent drive failure. I'd waste no time at all in getting a new drive and backing everything up.
You could then try reformatting the dicky drive, but I'd never trust it again…
Good luck,
Archie

External Hard Drive Becomes Read Only

I have a LaCie Hard Drive that Time Machine has been backing up to for about 4 days now. All of a sudden, the external hard drive is read only. When I go into Get Info for the hard drive, I can't even change the read/write permissions - it's all grayed out. This is the second time it's happened. The first time was on a Western Digital MyBook. TM fried that drive. At least this drive hasn't disappeared like the last time.
I've now changed the Time Machine backup to my second hard drive on my Mac Pro (which is screaming along, as opposed to the FW800 [!!] backup on my La Cie, whose file transfers are slo-o-o-w).
The idea behind backing up onto the external was so that if I ever needed to leave during a fire or earthquake, I could bring this with me and not worry if my computer was destroyed. Insurance would replace the computer, and I could replace my system.
If it weren't formatted properly, it wouldn't have been backing up for the last few days.
Can anyone help?
Message was edited by: Theresa Mesa

Thank you to everyone who has posted about this issue -- it just happened to me AGAIN this morning (this is my 3rd time), after I installed the 10.5.2 update. The first two times were right after I hooked up my external Iomega 500GB drive to use with Time Machine and I thought it was something I was doing. Then it seemed to work fine for a couple months so I thought the problem was over. Guess not! It is frustrating because I just lost about 2 months worth of backups. So finally I searched Apple's discussion forums and saw that I am not alone. However, no one was really posting a solution other than to say "reformat the drive".
So I did a Google search about this topic and encountered the following article. I have just gone through the steps he outlines and although I won't know for awhile if it works, I figure at this point it can't hurt to try. I hope this proves useful to others as well. (One note -- in his article, he says to skip the Erase tab and go right to the Partition tab. If you don't see the Partition tab, first erase your corrupt Time Machine backup disk and then follow his steps.)
http://gizmodo.com/gadgets/apple/leopard-disk-utility-format-issue-screws-with-t ime-machine-but-theres-an-easy-fix-316573.php
Cheers ~
Message was edited by: sneebish

External hard disc is read only on my MacBook air and I can't safe and export files on it, how can I change that

My external hard drive is read only on my MacBook air and I cand safe or export files to it. How can I change this so I can use the external hard drive to export my files and work on an other pc.

Eject and disconnect the drive (and its power supply, if it has a separate one) for a few moments, then restart it. Restart your Mac, then reconnect the drive.
If that doesn't help, the directory structure may be damaged. See if you can Repair it, per #6 in Using Disk Utility.

External Hard drive is suddenly Read only. Help!

I reformatted my I mac due to it being extremely slow. After reformat, the toshiba external hard drive that I have been using for months before with no problem, is now a read only. I have over 1TB of space available and I need to use it. Does anyone know what happened and how to fix it. I cant lose my information.

In the Finder, press the key combination shift-command-C, or select
Go ▹ Computer
from the menu bar. A window will open showing all mounted volumes. Select the one in question and open the Info window. What is shown as the Format in the General section?

External Hard drive suddenly will only read! How can I make it read/write again?

Hi folks,
I'm working with a Seagate FreeAgent GoFlex 320gb External Hard Drive on the imacs here at my university. I have it formatted to ExFAT so that I could use it with my pc as well but I've never had to so far so it's only ever been used on the uni imacs.
It's been fine for working on media projects until suddenly when i came back to uni after the Christmas break I went to continue working on a film project and realised the external hard drive now said read only??
One thing I did was to put all of my work from last semester (which is everything that was on the hard drive into a single folder) could that have caused the problem?
And does anyone know how i can reset my permissions to read/write without causing damage or risk to the files on the hard-drive as I can't clear the disk (i have no where else to store the 185gb of video footage).
I'd really appreciate it if anyone could tell me how i can fix it? I know how to do all of this on my pc but i've no idea with the mac as i only use it for my media projects here in the university.
Thanks!
DrF ;-)

Out of curiosity , will this method also work for an external drive formatted to NTFS.. I have a lot of data that I have nowhere to Float while re-formatting the drive , so If this method would allow me to keep the data and still fix the problem that would be great !! At the moment the drive is formatted to NTFS and permissions say Read/Write , but I can only Read.. Very Frustrating as my mac drive is running low on space and performance is being affected.. Any help appreicated !!

External WD Hard Drive suddenly Read only - Permissions Issue and Error 50

After completing a recent OS update, I noticed my WD, External HD was no longer accessible. When trying the run a backup, via Time Machine, I would see the following error: "Time Machine Error. The backup volume is read only." If I tried the open the back up drive to see individual files, I would receive an error suggesting I did not have sufficient privileges to access the drive. Apple tech. support suggested I lot into my computer as the "root" user. Once I did this, I still received the Time Machine error, but, could open the Back Up drive in Finder and access files. It was still impossible to add files to the back up drive, but, at least they're accessible. Lastly, I would click the "Get Info"option for the backup drive. Once in the Info window, I would choose the sharing and Permissions tab. All privileges are set to "Custom". When I try to change them to "Read/Write" I see the following error, "The Operation could not be completed. An expected error occurred (error code -50). The tech. Apple tech. support rep. was stumped. Any ideas? Thanks so much.

Your backups may be corrupted.
See #A6 in Time Machine - Troubleshooting (or use the link in *User Tips* at the top of this forum).

Time Machine once worked, now external hard drive is "read only"

I have a 2005 iMac G5, running OS X 10.5. Had some power issues, and reinstalled (and archived) my OS a couple of time.
Recently purchased Western Digital 1TB external hard drive for back up. It worked once or twice, but now shows "read only" status.
Disk Utility won't do anything, because it's read only (can't repair, erase, partition or convert).
Hard drive works on PC running Windows 7, and newer Mac with Snow Leopard, just not the one computer I need it for. Any suggestions?

This may help:
What to do if Time Machine reports you don't have permission
This was posted in the Apple Discussions by V.K. I have only modified it slightly to be more generic.
The problem seems to be that 10.5.6 changes permissions on a file so that even the root user doesn't have write peivileges. I have no idea why they did this. The workaround suggested in [an]other post will probably work, too, but i did something less drastic. Instead of deleting the file I changed permissions on it, and it worked just fine. An added benefit is that the permission change seems to stick, so you don't have to delete the file every time you change a drive.
[Open the Terminal application in your Utilities folder. At the prompt [enter] the following command:
sudo chmod 644 /volumes/"TM drive name"/.xxxxxxxxxxxx
The name of the file .xxxxxxxxxxxx is based on the MAC address of your computer and will be different for every computer. Put the name of the TM drive in the above and keep the quotes.
You'll have to enter your admin password (which you won't see) which is normal.
This was edited by Kappy just for cleanup.
Enable Finder to Show Invisible Files and Folders
Open the Terminal application in your Utilities folder. At the prompt enter or paste the following command line then press RETURN.
defaults write com.apple.finder AppleShowAllFiles TRUE
To turn off the display of invisible files and folders enter or paste the following command line and press RETURN.
defaults write com.apple.finder AppleShowAllFiles FALSE
Alternatively you can use one of the numerous third-party utilities such as TinkerTool or ShowHideInvisibleFiles - VersionTracker or MacUpdate.
Also visit the User Tips found at the top of this forum's Topics list: Time Machine User Tips.

I need a step-by-step plan: my WD external hard drive is 'read only'

Hi,
I hope someone can help me, because i'm in quite a pickle. I bought a WD 500 GB external hard drive a couple of months ago. I have a MacBook Pro version OS X 10.8.5. The problem I have now is that I haven't used my external hard drive for a couple of weeks now, until today (note: I bought this hard drive and used it for the first time on my macbook pro, never on windows before or any other laptop/pc), and all of a sudden I can only 'read' my hard drive, it suddenly seemed to have changed it settings by itself to 'you can read only' whilst I never did anything to the permission settings....
So i read a couple of questions about this online, and apparently im not the only one with this problem. but all the answers i read are way too complicated for me, with too much computer jargon. Therefore i just need a simple step-by-step answer, whatever i need to install or 'configure' in order to make this thing work again!!
Please can somebody help me??? I never used this thing for more than a month and only my macbook pro....help!! It cant be that i used this hard drive once and then all of a sudden it changes it's settings??
Thanks,
Daphne

If you can see the hard drive in Finder, select it, do a Get Info (command - I) and see what permissions you have in Sharing and Permissions. It should be Read/Write. If it isn't, unlock the padlock, and change it. Then look towards the top to see how the drive is formatted. It normally should be Mac OS Extended (Journaled).
If it is not that format, go to Applications/Utilities/Disk Utility. Open Disk Utility select the drive, select the erase partition, and after making sure the correct format is set, erase the drive. At the bottom the current format is shown. This will remove anything that was on the drive.

External Hard Drive is read only?? how do i change this?

ive just gotten a new external hard drive which i use a giant usb pretty much,
only problem is when i drag files into it to copy it tells me that "untitled" cant be modified.. also when i check its info im told that it is read only... how do figure out how to change this...
i need help please

Hi jami01
You need to reformat your new external drive in Disk Utility. Currently it will be formatted as NTFS which is a windows format and the Mac can read that but not write to it, hence your problems.
If you wish to use it solely with your Mac and not share it with a PC, then then choose the HFS+ format
Open Disk Utility,
-Select the external disk in the left panel. make sure you have selected the correct disk.
-Click the Erase tab
-Give the disk a name
-Select the Volume Format type to be HFS+
-Click Erase
If you wish to share it with a PC then Choose MS-DOS(FAT32) format
regards roam

NTFS External Hard Drive now read only

Hello Everyone,
For months I have been connecting a NTFS 1 TB Phantom Labs external hard drive to my mac book, to access my music collection, as well as store additional large files. Today, however, I found my external hard drive to be "read only," rather than read and write. Interestingly, the folder where I keep my music, also includes the lock image as the external hard drive icon.
When I look in Disk Utility, the Phantom Drive is originally listed as read/write. However, the mounting point, named disk2s1 is listed as read only.
Does anyone have any idea how to resolve this situation and return to the read/write status I originally enjoyed?
Thanks.

I have got the exact same problem!!
have a 320 seagate ext HD formatted as NTFS that I have been using for the last 3-4 months that suddenly became read only.
I'm running macfuse with 3G to read and write to the drive and prior to this have never had an issue.
Have another ext HD formatted as NTFS that reads and writes fine. I have tried disk utility but verify and first aid are greyed out for the seagate drive, One minute I was writing to my drive fine and next time I plugged it in Read only (yes I ejected properly as always)
Any ideas?? I hope it's not a re format and start again..

After moving iTunes, external drive sometimes becomes read-only after reboot

I had some system corruption a few weeks ago, and had to restore my system. As part of that prolonged effort, I decided to move my iPhoto Library and iTunes Library to external FW800 drives.
I had terrible problems initially with these drives mounting read-only. I found a relatively quick work-around, and that seemed to fix the problem. But I still have them periodically mount read-only, and I can't D/L iTunes updates, etc.
Why do they keep doing this on a reboot? Very frustrating, as I need to reboot as part of the fix, and I'm always in the middle of something else, and can't reboot at that time.

Oh, as part of this, not sure when the change was made, OSX used to keep the mounted volume name in /Volumes, even if the volume was ejected. Would cause an occasional problem - but very rare. I notice now that ML seems to create/delete these mountpoints automagically - and that's part of the problem. They get incorrect permissions when the volume mounts, and I (user I'm logged in as), can't write to the volume without some background shenanigans.
My process is this:
Unmount problem volume
Drop to terminal, and "sudo mkdir /Volumes/<mounted_volume_name>"
Remount volume via Disk Utility (you now get a "<mounted_volume_name> 1" - with CORRECT permissions)
Unmount the volume again
Remove the created directory (i.e. undo step 2)
Remount the volume - 99.9% of the time that seems to fix it.
Reboot to be sure - and it stays for a while - then at some point becomes a problem again.
Not sure if it's something in ML that's an issue - or something in iTunes or iPhoto (but can't see how they would affect the permissions when the system reboots and you login)

External drives mount as read only

I am running OS X 10.6, on a MacPro. Something happened recently to make my external hard drives mount as read only. The only way I've found to be able to fix them is to run Disk Utility every time I start up my computer. Does anyone have an solution to this?
Also every time I run the Disk Utility, at the end of the repairs it says "Updating boot support partitions for the volume as required." I do not know if this is related, but I haven't been able to find anything relevant in relation to my problem with the drives mounting as read only.
Message was edited by: HeatherK

You might give this a try:
Select the drive and Press COMMAND-I to open the Get Info window. At the bottom open the Ownership and Sharing section. Be sure the box labeled "Ignore permissions on this volume" is unchecked. If it is checked then click on the lock icon, authenticate, then uncheck that box. Close the window.
Open the Terminal application in your Utilities folder and at the prompt enter or paste the following:
sudo chown root:admin
Put a space after "admin" then drag the drive's icon into the Terminal window. Press RETURN. You will be prompted to enter your admin password which will not be echoed.
See if this fixes the problem.

My external USB drive became read-only

I migrated from a Macbook (black) to a new Macbook Pro (late 2008 model) a week ago. Everything seemed to work fine except that I can't write to an external USB drive (worked fine with the Macbook) from my new Macbook Pro. Disk utility indicated I only have read-only access and didn't give me a way to change the permissions. The drive still works normally (read-write) with the old Macbook.
The drive was formatted as Mac OS extended (journaled.) Both computers are running 10.5.5 when this happened. I have since upgraded my Macbook Pro to 10.5.6 but won't have an opportunity to test it with my drive till January.
I know I can re-format the drive with Macbook pro but I don't want to lose the data. I have no other storage to temporary hold the data (about 450G worth.) I tend to change computers every 6 months or so. This will continue to be a problem for me. I am looking for a nice permanent solution.
Thanks.

Welcome to Apple Discussions:
You probably do not have write access to the drive, if it came from a Mac with another account.
In a terminal run the command
ls -al /volumes
and see what permissions the drive has.
You should see something like
drwxrwxrwx 1 nero nero 16384 Dec 18 13:02 TravelDrive
Where "nero" is the name of the user who has access to the drive. Notice that on my drive, everyone has read, write, execute privileges on the drive.
Message was edited by: nerowolfe

External volume is suddenly read only

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