2015 MacBook Start Up Issue

Hi Gang.

I have been receiving the following message on my girlfriends Mac upon startup:

Any recommendations on how to solve?

She’s running:
12" MacBook 2015
macOS Big Sur

Many thanks indeed,



I would follow the instructions at the link below, including booting into the recovery system. There’s a link for how to do that on the webpage.
Hopefully it’s something that DiskUtility can repair!

Hi @JohnAtl

Thank you for your reply.

Bad news, I ran First Aid on all disks and in recovery mode too and no luck. We still have the same message appearing on booting up.

Any other ideas?

Really appreciate it :slightly_smiling_face:

this might be useful - do you see 2 data drives in disk util?

Hi @aardy, I thought this might be the case.

Thanks for your help :slight_smile:

If you are seeing 2 - did you see this message?


There’s likely no need to erase and all that. I just got off the phone with apple and they guided me through to the disk utility, Macintosh HD - Data had been duplicated and the second one was greyed out. they had me click on the greyed out Macintosh HD - Data and then click the “-” to remove the disk. It was removed and I restarted and it’s perfectly fine. Hope this helps.