Like many of you I upgraded a few weeks back from Catalina to Big Sur confident that there would be no issue. It's not my new thread on the issue but could not find my last post so decided to create a new one. He has reinstalled os Catalina hence me being able to email this today.ĭoes anyone have thoughts about what i can do from here as I would like to bring my iMac up to date but I do NOT want to go through this again and its already cost me a lot of money to be able to use my machine again.īig Sur upgrade and now Big issues Hi Apple Community,

He managed to recover all of my data onto an external 2Tb Toshiba drive (thank goodness) BUT he tried to reinstall Big Sur with no luck either. On Monday, I took my iMac to a repairer who did an excellent job in updating my iMac with a Samsung 2Tb SSD drive and maxed out my RAM. The bottom line is that having spent around 10 hours trying to reinstall big sur I kept getting the message 'application denied'.

I contact 4 apple support people who were helpful, we went through diagnostics, recovery etc etc. I tried over and over again to reboot with no luck. On rebooting it progressed to around 50% and stopped. Last Saturday my 2017 iMac 4k retina, crashed using the lasted Big Sur update. Can anyone offer help and guidance please?

Instal the new for apple CPU-Z 2.06.1