macOS Big Sur 11.5 update hangs

[M_Six]

Trying to install BS 11.5 on a 2020 iMac for the second time. It gets to "Preparing macOS Big Sur 11.5..." and "About 10 minutes remaining" and then hangs. First try I let it sit for well over an hour and it did nothing. This time around it's been sitting like that for 20 minutes. Any ideas?

 

[harryb2448]

Any chance this is on a Fusion drive?

iMac's Fusion drive not fully compatible with BigSur?

I have since 1,5 year an 2019 27" iMac. He came with an 2TB Fusion drive. Apple gave the promise that all the often used apps will be automatically stored on the SSD part of the Fusion drive. This was the truth with Mojave and Catalina. Cold boot took less than 10seconds to the login screen...

forums.macrumors.com

 

[M_Six]

Second time seems to have been the charm. It finally finished.

Not a fusion drive. 1TB SSD.

 

[chscag]

Yeah, it took quite a while for me too. It's tempting to reboot when that happens but you just have to be patient and let it do its thing.

 

[IWT]

Yeah, it took quite a while for me too. It's tempting to reboot when that happens but you just have to be patient and let it do its thing.

Absolutely! Go away and do something useful . Give it lots of time. Mine took around 35 minutes, maybe longer; but it worked first time.

Ian

 

[ferrarr]

My Mini hung on one of the restarts, for about 15 minutes. I just pressed and held the power vbutton and it went right to the login screen. I believe it happened the last update as well.

 

[Raz0rEdge]

I always do the updates overnight, so I never know how long it takes, but it's always done the next day.

 

[M_Six]

Maybe Apple should change the "About 10 minutes remaining" to "Go away and leave me alone."

 

[southchatham]

I updated My 2014 Mini today. It was a big leap, from Yosemite to Big Sur.

Working good now. But I had the same stall with 1 minute to go. After trying a few things I remebered the same issue years ago with Snow leopard on my Macbook.

All I did then and today is plug in Ethernet and it finished. So just connect through Ethernet.

PS. I tried to airdrop this photo and it transfered as HEIC, which shows grayed out when trying to upload here. I had to email it to myself to keep as a .jpg.

 

[IWT]

Well done,@southchatham.

You may just find macOS 11 Big Sur (BS) a touch slow given that your processor is only 1.4GHz and your RAM only 4GB.

But, hey, it's up and running and that's down to you.

Ian