iPad Air (5th Gen) external drive 'read only' error

You will need to reformat the USB drive - but before doing so, ensure that you have transferred any data from the drive that has not been backed-up elsewhere.

You can either reformat the USB drive using your iPad (requires iPadOS 18 or later), or use a Windows PC or a Mac computer.

From your iPad, connect your external USB storage via an appropriate USB-C hub or Adapter. Using the Files App, identify the external storage device from sidebar - then touch-and-hold the associated USB device icon to expose the Action Menu:

From the menu, select the required device format - then tap the red Erase button:

You should note that exFAT is supported by iPadOS, Windows PC and Mac. APFS is not supported by Windows PC.

If instead you reformat the drive using a Windows PC or Mac, your iPad supports FAT, FAT32, exFAT (FAT64), APFS or HFS+ with a single partition. Microsoft NTFS and other proprietary formats are not supported by iPadOS or Mac.

The most flexible format to choose, for compatibility between various computer Operating Systems, would be exFAT.

If the folders on your USB drive are read-only, you will need to set them to read-write using a computer. iPadOS lacks the native ability to remove or change file/folder permissions.

Windows (10/11/XP/7)

If you receive an "Access Denied" error, follow these steps on your Windows computer:

1. Locate the Folder: Right-click the folder in File Explorer and choose Properties.
2. Security Tab: Select the Security tab. If you do not see this, you may need to disable "Simple File Sharing".
3. Edit Permissions: Click Edit to change permissions for your user account. Ensure your user has Full Control or Read & Write checked.
4. Apply to Subfolders: Click Advanced and ensure the permissions are set to "Replace permission entries on all child objects" to apply changes to all subfolders. 

macOS

1. Locate the Folder: Find the folder in Finder, right-click it, and select Get Info.
2. Sharing & Permissions: Scroll down to the Sharing & Permissions section.
3. Unlock: Click the padlock icon to make changes.
4. Change Permissions: Add your user account or select "Everyone" and set it to Read & Write.
5. Apply to Subfolders: Click the gear wheel icon and select Apply to enclosed items. 

Instead of saving files directly, are you able to create a folder on the target drive? If you can create a folder, try saving your files to the folder instead.

Without delving deeply into the technical aspects, depending upon the drive type and formatting, you may not be able to save individual files directly to the root directory of the drive. In such cases you can usually create folders within the root directly, below which files can be saved.

Otherwise, the drive may need to be reformatted. For iPad, your USB-connected storage must have a single data partition - and be formatted as FAT32, exFAT or APFS. iPad generally cannot read multi-partition devices, or proprietary device formats (such as NTFS).

It may be that the USB drive is locked to a computer and needs to be formatted from within Mac OS or iPad OS to work with the iPad. If you need more help, I recommend going into an Apple Store; they should be able to sort it out for you!

Thanks

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In context of your current difficulty - specifically that your USB storage is currently read-only - re-formatting the drive (as suggested) should resolve the problem, leaving you with a freshly formatted device with read/write permissions.

You initially made reference to an "external hard drive" and attempting to save videos via an unspecified USB Adapter. Now you mention SD card.

Perhaps you should clearly explain what you are attempting to transfer, where the files are currently located, and to where you are attempting to copy/move these files. Specific details of any external hardware or Adapters may help to clarify.

Please remember - the only information that contributors here are aware will be the explicit information that you provide. What might appear immediately obvious to you, in context of what is in front of you, is perhaps not obvious to others here.

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You're very welcome. I'm delighted that, as anticipated, the problem has been successfully resolved.