Time Machine problems after upgrading to 11.4

[bailorg]

I upgraded to 11.4 yesterday and later that evening Time Machine stopped working. Specifically, I'm getting an error that says my Time Machine drive is "read-only." I ran First Aid in Disk Utility and it says that the volume cannot be repaired and to back up what I can ASAP.

I tried resetting the computer and unplugging and plugging back in the drive, but I'm still getting the same results.

Is there anything else I should try before going out and buying a new Time Machine drive?

Anyone else having problems after upgrading to 11.4?

FWIW, I'm using a 2017 27" iMac and an at least 5 year old WD external drive (I recognize it really could be a dying drive) for Time Machine.

 

[Apple_Robert]

I have gotten that message before with a WD Passport drive. I tried reformatting and that didn't work. I had to get a new drive.

I would backup that drive to another if you can, and then try reformatting before looking at new drives.

 

[gilby101]

I upgraded to 11.4 yesterday. I'm getting an error that says my Time Machine drive is "read-only." I ran First Aid in Disk Utility and it says that the volume cannot be repaired and to back up what I can ASAP.

Was that upgrade from 11.3 or was it from something much older?

Can you read the HDD?

Please provide the output from the Terminal command diskutil list

 

[bailorg]

The upgrade was from 11.3.

I can still read from the HDD, but I'm still getting the "Time Machine couldn't back up to "Time Machine" with the detail claiming it is read-only

Here is the result of the Terminal command:

 

[gilby101]

Apple Partition Map is a bit of a surprise. My understanding is that TM requires a drive partitions with GUID Partition Map. So I am not surprised that TM fails, rather surprised that it was working with macOS 11.3. So I must be wrong about that! I have seen nothing to suggest that 11.4 changes anything.

I assume there is free space.

If you do decide to get a new HDD (and I would):
Keep the old one, in case you need to restore some old files.
Format the new one as GUID Partition Map and APFS.