Hello,
my external Disk is no more writeble.
How to make it writable again?
Suggestions welcome. Thanks.
Not sure if you are saying it is ignoring the Read & Write privilege, or that it changed the “everyone” privilege. If it’s the “everyone” privilege, then I don’t know if you missed that you have to Unlock it by clicking the padlock on the lower right of the window and entering your system password. That’s what you have to do to change the privileges.
Now if you did all that, and even though you are “wheel” or “system”, you still cannot write to it - that’s another issue. But I don’t want to assume the simple steps have been tried.
Thank you, Paul. It was read&write, and then it became read only.
Yes, I already had unlocked the disk and entered my pw, but trying to set “everyone” as read&write a warning appeared saying that I had no priviledge to do so.
BT. what I’d avoid is reformatting the disk.
What is the MacOS version ? Apple introduced a change where external drives are by default Read-only. One needs to change a setting to be able to write to an external disk, but I can’t tell what it is - I don’t have access to a Mac with a recent version of MacOS.
Hum, I may be wrong, it could be the OS blocks booting from an external disk.
Sorry 
Well, there is a little possibility, that the file system is damaged and turned to read-only.
Or that an SSD reached the end of it’s live time and turned to read-only, too.
That would be if no more blocks can be written.
In both cases, you better copy the content to a different disk.
And if it is the file system, you can reformat the disk.
did you start a time machine backup on this external drive ? if so it is blocked by macos
the only way I know then is to format the drive again.
you can also using the terminal make a new folder at the drive root, set the permissions to everyone
and it could work inside this new folder.
If you want an external drive as a Time Machine drive AND other storage, then create a folder on the external drive BEFORE you set it as an a Time Machine drive. This will keep that folder as writable.
I had this ones with an external SSD drive.
In my case the solution was to connect the SSD drive into a Windows system and then back in my MBP. And it suddenly worked again.
Did you check the other content of that drive? Probably, the read-only applies to the root volume of that drive only.
This. I’ve had this happen and I still don’t know why. The rest of the disk was writable, but I could no longer make changes to the root. I’ve since moved to a larger drive and reformatted the old one, so I can no longer experiment.
Was it formatted with APFS? I’ve had real problems with external drives which were formatted with APFS.
I’ve went back to HFS+ for external volumes for now. So far (knock on wood) none of the same issues have occurred. Same drives, same enclosures, same OS version/install. So it feels like APFS is the culprit, which is… ¯\(ツ)/¯
Sorry for not answering but yesterday I was busy elsewhere. Back to the external SSD (LaCie) that is formatted as Mac OS Extended.
Actally I have got two external drives for backup, and their content is exactly the same.
Neither disk uses TimeMachine: my backups are done by drag-n-dropping two folders containing my stuff (Xojo projects and translations).
After reading all these suggestions, when I saw that all the ways were blocked I decided to re-initialize the volume. I was really surprised when after clicking the “Erase” button in DiskUtility I got this warning message:
How old is the drive? It could be failing?
5 months. But since I got it from Italy but I live in Asia it may take some time to find somebody taking it back to Italy…
when you erase the disk, you can choose the disk format (apfs, macos extended etc) and also the partition map.
what do you have as partition map ? it should be apple partition map
also you can try to select another format like extfs, then come back to macos extended.
Tried all possible combinations: fact is that, as I said, the erase process stops and shows the warning screenshot above).
Meanwhile I took the disk to a Windows PC shop where the technicians after trying a lot could not achieve any positive result; they too could not erase the device.
Therefore the story unfortunatelly ends here.
unless there is a command in Terminal to erase disks…
there are commands to erase a disk using terminal look at diskutil and its options
but if you can’t erase it with disk utility, you will not be able to erase it with command line.
Your words confirm what I thought: no way out.
Thanks.
Means: Try with ExtFS first, and then reformat as HFS+ if required.
