Quick Tip: Solving "Read Only" External Drive Problems on Your Mac 

10 years later this video is still helpful.

9 years later and this video is still helpful. Recently switched to Mac and was having a huge issue with my external drive until I found this.

Well obviously I knew the solution was to format it. That's why I came to this video to find an alternative way without having to delete 500GB worth of storage

any way to do this without formatting the disk? my files have the total of 800 gigabytes, it will take lot of time

Thanks man from me in 2023

Posted 9 years ago and it’s the best “How to” video I have ever watched on RU-vid. Thanks a lot!

You sir deserve every bit of ad revenue this video brings your direction. I should've known to go this route, but I needed some reassurance. Simple solution. Great tutorial. Appreciate it!

Wow, they say, Old is Gold. A video almost 7 years ago, you made saved my day. I couldn't find any other clip better than this. Thank you so much.

pause on 2:56, messages: would you like to hook up? lol

This video is perfect: the problem and resolution are clearly stated and shown without extraneous info. It is professionally produced and is easy to follow and understand. As a former technical writer, I applaud Tuts+ -- and I thank you for solving my external hard drive issue!

Amazingly helpful! This helped me not only to immediately solve my problem, but have a fundamental understanding of the problem in the first place. Well spoken and easy to follow for anyone! Thank you VERY much!!!

but what if you have 800gb files in your HDD out of 1tb and you have to make it work with a Mac? This is where my frustration is right now.

What do you do if the erase button is grayed out. I was downloading a large file to my Gorilla Drive and it unmounted and now i can't repair or erase. I tried on a PC to and it says permissions error. Any thoughts on how to solve this one. Is there a force format on a Mac?

This was exactly what I needed! Ah! Thank you so much, perfectly clear explanation! =D

Excellent tutorial!! I wish they were all this clear and simple and perfectly paced. Thank you!

Does this mean that if I typically copy over larger files (larger than 4gb), I have to reformat the drive to NTFS on windows everytime?

My erase button is grayed out. The volume format is as well, but it says it is MS-DOS (FAT). WHen I clicked on Get Info, it says it is read only. How can I fix this?

Thanks - we just had the problem yesterday - thanks for the solution.

WOW. This is EXACTLY what I needed to know. Thank you for the clear tutorial. It worked PERFECTLY with no headaches or effort on my part. :)

Simple and clear tutorial, explain key points and solutions to the point. Very professional, thank you.

My Sandisk Usb can only read and if i try to erase, it says "Erase process has failed. click done to continue".

when i click erase, it says "Volume Erase failed with the error: Couldn’t unmount disk." what can i do

Thank you so much!! 6 years later and the information still essentially worked (Mac OS version is updated and the Erase column detail has changed some) but you saved the day!

hi, i have 2 external drives, 1TB and 2TB. One for beackups and second for files. Everythink works good for at least a year till I resently upgrade to macOS Mojave version. Now I can’t write on both of them. Any help to fix it without formating ?

I've been using my external drives for so long and my mac use to read them, i just upgrade to el capitan with a clean install and now it won't let me modify one of the drives and the other one won't read. so in my case i don't think the solution should be to format the drives, since they worked before in my mac.

This isn't any good because my external hard drive is the problem and there's so much on there that I can't just copy it across to my mac.

before erasing your data on the external hard drive, in the area where you reformat and rename, I have another drop down menu called scheme, what do you change that to?

can i format my external hard drive with its existing partition one at a time? if so, can i back up the other partition's content to the other first? thanks!

TL;DW (too long, didn't watch): Copy all stuff from your drive to desktop or wherever Reformat drive to MS-DOS or ExFat for PC/Mac, or Mac OSX Journaled for Mac only Copy all stuff back to your drive Problem solved

Thank you! You saved the day!

The video is very straight forward, simple and helpful. Solved my hard drive problem on the spot! Thank you!

my usb flash disc is on mac os extended journaled and its suddenly became a read only flash. I try with disk utility to erase and format at ms dos but all the choices are disabled. what can i do ?

I've got a different problem. My external drive's in MS-Dos Format and i didn't get the option to erase. What do i do in that case?

what do i do if it wont give me the option to erase?

On 3:15 of your video, I selected the flash drive I want to erase and want to change the format, but I am unable to access the format. It is blocked. What should I do?

wow, that was very very useful tutorial. for a whole day I was so confuse how to fix my problem. Thanks!!!!

Thank you!!!!! for posting this Video.

-___- I was hoping I wouldn't have to format, oh well...

if i format it for mac(as u hv told) then ll be able to use it on win 10 pc?i want to use tje hard driver in both mac and win 10 laptop.pls suggest.

9 years later you are still helping people. Thanks a lot!

This was exactly what was looking for and was explained prefectly.

this solution is not a viable option for me.. you see i use a 3TB external hardrive which works on every other operating system in the world except this. now copying over 3TB of stuff is impossible as my laptop containts a 3x128gb SSD's in raid and 1Tb internal hardrive. i have about over 2TB of information on the external. really pissed off right now.

I'm doing editing in Final Cut Pro on a WD Elements Portable HDD. How should it be formatted? I heard ExFAT is bad.

So my format is already in Mac OS Extended, but for some reason I still have only reading privileges. Does that mean something is wrong with my computer, or with the external hard drive? It was working just days ago.

OMG! Thank you for posting this video! Life saver! HUGE THUMBS UP!!! + new subscriber!

Great info, but what about the 4GB file size limit of FAT 32? I advise my customers to make their decision on how to store their files based on the types of files that they're storing, and how often they really need to connect a drive to a Windows PC. The best solution in my opinion is to use dedicated drives for each platform, or to use software that allows the Mac to read and write NTFS. Also, when a Windows PC shares a drive over the network, the Mac won't have any NTFS issues at all.

I did what you said, but now i have custom access under the ( sharing & permissions ), i can drag folders to the hard disk now " which i couldn't do before i watched your tutorial " but i don't know if it is a problem or not . And i wanna make sure if it's safe to load all of our family photos in it .

when you format to MSDOS am i able to copy files bigger than 4GB like i do with a FAT format?

Thank you thank you for saving me a giant headache !

This literally saved me! Thank you so much!

Thank you for taking your time in making this video. I had a horrible time with this issue for the past 9 months. THANKS!

hi mate . How can I open folder in flash memory that protected by usb copy protection software and that usb copy protection software for Windows not for Mac. plus I don't wanna delete the folder I only need that protector app in flash memory works on Mac. thanx

what if you don't want to *format your drive

this video is very helpful but could have been like 2 minutes shorter :D

Hi, I understand your video in how to change the "read only " . But my hard drive has 250GB in storage so it won't fit all to transfer it to my desktop , so do you have other option for me to do it ?

Out of every video online this is the only video that actually helped me solve my issue. Thank you so much for posting and sharing.

Are you kidding me? Title is a bit misleading...I thought this was a quick tip to solve the problem, not erase the drive with date on it! I knew how to do that....!

THANK YOU FOR THIS! Straight to the point lol

My Mac only shows ExFAT. But I need to use the hard drive for both Mac and Windows. Does ExFAT still work as MS-DOS? Thanks!

Does the Cross-compatibility (MS-DOS) mode allows us to copy files larger than 4GB in mac ?

All I did was update my mac to OS Sierra and this what happens? Now I have to reformat a 3TB hard drive? Apple is becoming a joke now wtf... Apple please note that either you get with the future or be left behind. You are losing your touch and I am becoming less of a fan as the days go by!!!!!! Apple you do nothing but make my life more difficult than it has to be! I am very very upset!!!!!

This one is lame and the most stupid suggestion ever. I have TB's of data on my storage device and my mac has barely 500GB. This is not even a workaround in the situation. I used the steps below and it worked on Yosemite too (The drive will not pop on the desktop but it shows in finder in my home folder and is writeable a) open the terminal (or iTerm, or whatever) and type: mount They will show a list with all the devices in your computer. Last things last, if you just plugged your hard drive, it will be the last line. In case not, just look by the name of your HDD. b) Copy the /dev/diskXXsY related with your hard drive (in my case, /dev/disk24s1) c) type: sudo umount /Volumes/HARDDRIVENAME (whatever is the name of your HDD. You can press tab to autocomplete, once spaces are covered with backlashes) d) type: mkdir ntfs e) type: sudo mount -o rw,auto,nobrowse -t ntfs /dev/disk24s1 ntfs (again, disk24s1 was my case, the step b will show you the route of your HDD (Credits joaprp on learnaholic for the original post)

Hi, I have a similar problem with my HDD Western Digital My Passport. I used it to copy some file on a Machintos computer, it worked, but when i tried on my computer PC Windows 10 it show like a new device, empty. I think someting happen with the software, maybe automatic update on the mac version. The strangest thing is now it's not working on both. I might say the hdd is not a mac version . Please help me what should I do

Hi.... My USB is formatted in MS-DOS (FAT32). I have followed every step that you have shown in the video but it says Erase not successful. How do I remove the write protection ??

Not helping at all. I don't need your help to ERASE a drive!!! C'mon!!!

EASY AS HELL , for the ppl who's format button is greyed out and having problems with permission issues !!! I just found out the solution by myself while i was looking for the answer. 1 > Connect your drive , 2 > Go to time machine , 3 > Turn Time Machine On for the drive that you're having problem with , 4 > The Time Machine will automatically format the Hard Drive into MacOS extended and all the restrictions will be gone with the process , 5 > Now you have the drive that you can do whatever you want and turn back off the Time Machine if u wish !!! Easy isn't ??? ENJOY :D :D :D

Thanks man, this is great. It is one of the only tutorials that have told me exactly what I wanted and needed to know! You have a good day sir.

also applies to a network shared disk from another PC? I have the same problem

This idiot's solution is only for a close to empty or new HD, unless you don't mind transferring data, waiting and formatting. My Samsung external 2TB HD was more than half full, but I just found out that it has its default utilities pre-installed. Inside there was an NTFS driver just for this very problem. Installed it, restarted the mac and everything finally worked. So check your external HD utilities, it might have this NTFS driver file for mac.

I've been trying to figure this out for months, and you're video was awesome. Thank you!

This was a super informative and helpful video! Mission accomplished. So glad I found it!

My photos won't open even though I've got permissions. Any idea what's going wrong? iMac using Toshiba external SSD. The permissions went very suddenly, BTW. It worked before, now I can't access any photos on the external SSD.

after searching high and low for a solution to my external hard drive, this is the ONLY tutorial that explained just what I needed! thank you so so much!

THANK YOU SO MUCH, THIS HAS JUST SAVED MY LIFE!

I have 2TB external hard disk and 251 GB Mac , any suggestion how to format my external HDD without loosing data

After several days of frustration, several articles and You Tube videos, I came across this video; he nailed the problem and the solution. What a relief. You know what you are doing. Go to the head of the class!

any ideas on how to make my usb writable as when i get to disk utility and try to erase, its just greyed out?!

Very helpful, but I need to know how to copy the files, which it won't let me do, before I make the disk compatible with a Mac. Can you please advise on how to do this?

PLEASE HELP ME! And if I can not format the drive? You have any other solution? I can not format because I have no other HD. Thanks!

Will my music files that are already in itunes still be recognized by itunes under the new format ?

So easy, very helpful. Great work!

Hi there! So i followed all of your steps and I’ve selected to erase it with first that one that you suggested and than also Exfat but none of them worked, and ut still just showing me read only for my usb drive :( could i ask if you ever came across this problem yourself? And how did you fix it? Thank you!

Mine just says (after pressing erase) that the process has failed, and when I select the show details tab, it says "couldn't modify partition map". Can someone please tell me what this means and how to fix it.

Perfect explanation. You made this issue incredibly easy to solve.

i dont want to erase files. it's too many. is there another way? because it reads on a different mac but not the newer one

Thanks for this! I have two clunky old fashioned external hard drives and one shiny new one an eighth of the size that can fit everything on it... minimalist dramas ensued when I transferred all my files then couldn't erase the old drives before donating them! Such an easy fix well explained! cheers!

Really good! Thanks for this simple, short, useful tutorial

This video is so helpful thank you, however when I tried to put everything back on my drive, after formatting, it says that it can't be copied as the file is too large for the volumes formatting. Any advice ?

but what if you have tons of data on your external hard drive and you don't have much time to move it to some other drive , what if you have to fix it while having all the data on board....any solution???

I've seen so many videos but this is the best one so far and it actually worked, thank you so much!

I changed the file system to AFPS and I changed the permission as well. Still it is read only. Can you help?

i have a external hard drive one day it went to read only on my mac i cant do what you did on the video it has all my kids photos what can i do to save them ?

So does it mean I’m still able to move and add files as long as it’s done on a windows computer?

How do i re install mac os sierra into my 08 imac? It wont allow me to re install it says not writable?

l am having a different issue that makes no sense. l have a flash drive that l can write on, and read from, but when l pull a file from iTunes and put it on the drive it converts to a corrupted file. it writes pictures, and videos/movies just fine, but iTunes just hits the wrong button or something. iTunes can write on this drive form my other computers though. l have even reformatted the drive twice and converted the music l want to transfer in to different formats, but it still ends up corrupted. the weirdest part is other drives take the files just fine with no corruption. its just this certain drive on this certain machine that has the issue.

I get "Couldn't modify partition map. : (-69874)" , can you help with this error

I tried this and yet it told me that "Erase process has failed. Click Done to continue." Can someone help me on this?

hello i have a problem, it owrks on one mac but and another one stilla has "read only" and I cant fix it, please help.

Man thank you sooooo much i'm a actor/filmmaker and i was going crazy trying to figure out the problem God Bless you!

I was going crazy trying to figure this out. Thank you so so much, it worked a treat ❤