HDD encrypted can't update macos 10.15.7 How to solve the problem ?

Hey O_087!

To confirm, you’re trying to update from 10.15.6 to 10.15.7? Or to the new Big Sur?

I’d say, either way, I’d start up in safe mode and try again:

https://support.apple.com/guide/mac-help/start-up-your-mac-in-safe-mode-mh21245/mac

Otherwise, also if trying to get to 10.15.7, I’d try here:

https://support.apple.com/kb/DL2051

Also, if you need to, you can Reinstall Mac OS from Internet Recovery to download the latest available OS version, (Would now be Big Sur):

https://support.apple.com/en-us/HT204904

For the OS version you have now, you’d startup while holding Command Option R.

Best of luck!

Hey again!

Can you say what happens when you click on “Unlock” and you enter your Admin password?

I take it, since it says it’s “Decrypting” that you’ve, yourself disabled FileVault in:

System Preferences > Security and Privacy?

Also, are there other admins on your Mac? I ask because other admins might have been enabled to change FileVault settings, and it sounds like a FileVault issue.

I take it, as it’s an iMac, it’s been plugged in this whole time, which is also needed to decrypt.

If you open Terminal in Finder > Applications > Utilities:

Type:

diskutil apfs list

In the results you should see your Macintosh HD, usually as a disk0s2 or disk 1s2 etc.

Anyhow there it SHOULD also show the progress of the “Decryption” if it’s in fact still decrypting which shouldn’t take that long, but it can at times takes several days, so that may show progress.

Anyhow let me know and I’ll do what I can to help! (Worst comes to worse and you can’t get past this decryption problem, if you have a backup, you can erase the main drive and reinstall the OS, and migrate your data back, but that’s a last resort of course, but would most likely fix it).

Best!

Hey again! No problem. Yes, it may come down to that, erasing it, unfortunately if the system still thinks it’s encrypted after disabling FV and keeping it plugged in after some time.

However, can you tell me, in that last picture of Disk Utility, if you took that while logged in? Or booted to recovery mode?