Want to highlight a helpful answer? Upvote!
Did someone help you, or did an answer or User Tip resolve your issue? Upvote by selecting the upvote arrow. Your feedback helps others! Learn more about when to upvote >
Did someone help you, or did an answer or User Tip resolve your issue? Upvote by selecting the upvote arrow. Your feedback helps others! Learn more about when to upvote >
Am using a 2017 IMac (27") 3.8 Ghz i5 with 16GB DDR4
running Monterey 12.7.4
Tried to do a reinstall using recovery mode (cmd R)
It tells me I can't do it and gives me this message
"com.apple.buildinfo.preflighterror.error21
I looked up error 21 and it does not help me.
Any suggestions?
iMac (2017 – 2020)
Hi,
I think your internal HDD recovery partition is corrupting, you should run FirstAid on internal drive and reformat HDD in APFS with DiskUtility.
Then try to reinstall macOS on the internal drive which could solve your issue.
Won't let me reinstall Monterey
