macOS Big Sur error (-69461)

[ThoDis]

Hello,

I was updating from Mojave 10.14.6 to Big Sur and got the following error at 12m countdown.

macOS Big Sur error (-69461)​

Tried to run safe mode but did not work.

Anyone else encountered the same issue?

Thank you

 

[KoolAid-Drink]

Was the installer running in its "iOS-style" mode (full screen, progress bar and Apple logo), then the more traditional macOS installer popped up, with the mouse pointer and menu bar, and the error message?

If so, seems like a failed installation of some kind. I'd try a reinstall, but first do a disk check using Disk Utility.