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2pods2 Author

Level 1

16 points

Time Machine tells me disk is not available

Although Time Machine backs up my files on a daily basis, However it stops and gives me the following message everytime it gets to 261gb on disk or 73 backups, whichever happens first.

"Time Machine couldn't complete the backup, as the disk is not available@

Said disk is a external WD 3tb usb3 disk with plenty of space left, is solely devoted to Time Machine, was formatted on my M2 Max Studio.

I've run diagnostics on it, and it reports as OK, I've tried it in every usb/thunderbolt port on the machine, also in a usb 3 hub. It's installed OK, as I can see the backups.

It's formatted as a one big partition of 2.8tb quota.

Twice, I've reformatted it, started again, and it runs perfectly.....until it hits one of the two points above.

I'm mystified.

I'm running Sonoma 14.5

Mac Studio

Posted on Jun 14, 2024 8:29 AM

Top-ranking reply

Grant Bennet-Alder

Level 10

132,763 points

Posted on Jul 12, 2024 9:50 AM

it is possible that your drive could be encountering Bad Blocks. The free trial of DriveDx could tell you that.

You check it error counters for 'Pending sectors'. That confusing term is the count of blocks suspected BAD, but as yet un-repaired (by substituting a known-good spare block).

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27 replies

Jun 17, 2024 8:29 AM in response to 2pods2

if you suspect that the time machine DRIVE might be giving you a hard time, you can ADD an additional time machine destination drive at any time, and Time machine will create a new, stand alone backup set on that drive staring with right now.

When Time machine runs, backups will alternate -- every other backup goes to every-other drive, and any drive can be removed at any time. After the new drive gets going, the old drive could be removed, repaired, erased, or anything you like, and you are not left "working without a net" in the meantime.