How to change folder permissions on an MS-DOS (FAT) external drive with Read Only restrictions?

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Level 1

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How to change folder permissions on an MS-DOS (FAT) external drive with Read Only restrictions?

I have an external drive the folders in which are restricted to Read only. The drive is formatted as (MS-DOS (FAT) and the permissions are shown as Read only with no other options showing to permit me to change.

All the available guidance on line so far merely refers to selecting an alternative choice which of course none is displayed.

How can I resolve my requirement to edit the content of the folders?

[Edited by Moderator]

Original Title: Changing Folder Permissions

MacBook Pro (2021)

Posted on Jan 17, 2026 10:02 AM

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Answer 1

Top-ranking reply

MartinR

Level 7

24,366 points

Jan 17, 2026 11:36 AM in response to PaulSG

It is not normal for a FAT32 drive to appear as Read Only. It suggests that the drive is failing, as do the results from First Aid.

As @Neil already indicated, you should copy the contents of the drive to a new drive (and if on a Mac, the new drive should be formatted as APFS). And if this is currently your only backup you should copy to 2 new drives not just 1.

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Answer 2

Niel

Level 10

741,881 points

Jan 17, 2026 10:05 AM in response to PaulSG

Try using the Disk Utility's First Aid function on it. If that's not an option or doesn't work, the drive is either locked through a physical switch or has sensed that it's about to fail.

(262485)

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Answer 3

PaulSG Author

Level 1

34 points

Jan 17, 2026 2:30 PM in response to PaulSG

Thanks all for ther advice. I have copied the content of the external drive to my MacBook desktop and it appears t be read & write - no idea why but obviously now accessible as I wanted. Learn something everyday!!

However, when it comes to erasing the dodgy external drive I've run into a blank wall. When I open Disk Utility the erase function is not accessible. How can I erase the content? (saved elsewhere). Of course I might just resort to a 14lb lump hammer!!!

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Answer 4

Niel

Level 10

741,881 points

Jan 17, 2026 10:46 AM in response to PaulSG

1. Move the data on it to another drive and then erase the first one.

2. Its components wearing out. This will eventually happen to all drives.

(262476)

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Answer 5

PaulSG Author

Level 1

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Jan 17, 2026 10:36 AM in response to Niel

So, tried that and this is the result. Where might I find the "physical switch" and precisely what do you mean by the drive failing please?

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Answer 6

Niel

Level 10

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Jan 17, 2026 2:35 PM in response to PaulSG

Select Backup Pics instead of Macintosh HD.

(262488)

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Answer 7

PaulSG Author

Level 1

34 points

Jan 17, 2026 3:26 PM in response to Niel

Good point but I highlight the ext drive icon on my MacBook desktop / select Disk Utility / ….. and just get the Macintosh HD page; so not seeing how else I can “Select Backup Pics” instead.

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Answer 8

Niel

Level 10

741,881 points

Jan 17, 2026 3:28 PM in response to PaulSG

Click on View and select it in the Disk Utility's sidebar.

(262490)

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Answer 9

MartinR

Level 7

24,366 points

Jan 17, 2026 4:45 PM in response to PaulSG

Open Disk Utility. Then do View > Show All Devices. Select the drive in the left pane. Then you can reformat the drive. Assuming you are going to reformat it as APFS be sure to also select GUID Partition Scheme.

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