Re: iMac thinks it is new machine Ira L 12/05/23 06:25 PM
Originally Posted by ryck
When I selected reinstall Ventura, I was presented with images of my Macintosh HD and my two backup disks but not Time Machine. An attempt to install on Macintosh HD got, you guessed it, "com.apple.Buildinfo.preflight.error error 21"

If I am understanding you correctly, at this point you should not be presented with your Time Machine drive. I think you are being asked where do you want to install Ventura, and your TM drive should not be an option. The fact that you selected your Macintosh HD and it was a no go (same error message as before) seems to indicate a hard drive problem. My suggestion would be along the lines of Artie's—try installing with an installer downloaded from the App Store. Failing that, and here is where it is very easy for me to suggest other people screw up their own setup wink , do an erase of your Mac HD via Command-R and reinstall the System from there too, then bring over all your stuff from your (very good) Time Machine backup. This last suggestion is also what Apple recommends as the last resort if the previous stuff (my link in the previous post) does not work.

Hmm, maybe your problem is really hardware related. Try running Apple's Diagnostic Tests and see if anything shows up.
16 87 Read More