I'd like to install the emergency patch that Apple just issued. The advice is to upgrade to 11.6. I'm currently running Mojave 10.14.6. I've tried installing Big Sur many times, but the screen tells me the installation will take at least 12 hours. I

This method may seem unnecessary but sometimes the Router Restart clears Network issues from ISP to Apple Servers

1 - Shutdown Router.

2 - Shutdown computer and disconnect all External Drives.

3 - Restart Router.

4 - Connect to Router via Ethernet Cable. If via Wifi - Disconnect all other Devices using the Wifi - want the Maximum Bandwidth only for this computer.

5 - Restart computer in  Safe Mode. It does a Repair Disk, Clear System Cache files and only load Apple Software, extensions and Fonts

6 - Will load slowly - Normal.

7 - Once Logged in - using Safari Only  Get macOS Big Sur.

8 - Then click the Get button or iCloud download icon.

Here's a better question: why isn't there a Security Update for Mojave 10.14.6 available? There's already one for Catalina. The only update I had this morning was a Safari update. Mojave is still being supported (at least until Monterey lands...)

why isn't there a Security Update for Mojave 10.14.6 available?

You are asking the wrong people. We are not Apple but end users like you. We get no more "why" reasons than you.

SUs don't always release at the same time. I've had times when the old OS version got updates several days after the initial releases. In business history, the number of users per platform drive most corporate decisions in matters like that.

However, both my Mojave Macs showed only an upgrade to Safari this morning that appears to a supplemental version of 14.1.2 that had already been released a couple of weeks ago. That may be part of the fix. I recommend applying that for now and continue checking Software Updated for a full patch.

You will need a 2014 or later iMac and 35.5 GB of available storage before you can install Big Sur. The only security update for Mojave was the replacement Safari 14.1.2 security update. Had the issues resulting in security updates to Catalina or Big Sur existed with Mojave, there would have been more than just a Safari security update on Mojave.

Stay where you are unless you have done proper planning regarding strictly 64-bit application, printer/scanner driver support on Big Sur, and the possibility of application and printer/scanner disruption on Big Sur without that due diligence planning.

BDAqua,I downloaded Big Sur installation programme to my MacBook Air, but couldn't complete the install due to isuffucient disk space, even after binning every app I could bin. So, I moved the Big Sur install program to an External Hard Drive. Unfortunately, it wouldn't open from the EHD.

Hey Wells Hayes!

✣ First off, what type of Mac computer do you have. We need to know if it is eligible to download Big Sur. To check, click on the Apple menu > About this Mac, and then see what type of Mac / MacBook you have (reply back with this).

✣ Second, and the most important, back that computer up - both on the cloud and to an external drive (in case things get bumpy), and we'll converse some more.

Stay tuned, you're doing great, Wells!

macOS Big Sur - Technical Specifications

General Requirements

OS X 10.9 or later

4GB of memory

35.5GB available storage on macOS Sierra or later*

Some features require an Apple ID; terms apply.

Some features require a compatible internet service provider; fees may apply.

Mac Hardware Requirements

For details about your Mac model, click the Apple icon at the top left of your screen and choose About This Mac. These Mac models are compatible with macOS Big Sur:

MacBook (2015 or later)

MacBook Air (2013 or later)

MacBook Pro (Late 2013 or later)

Mac mini (2014 or later)

iMac (2014 or later)

iMac Pro (2017 or later)

Mac Pro (2013 or later)

Hi BDAqua,

Yes, I had read that, but I just couldn't get it to work.

I'm not super techy with such fundamental upgrades.

I've managed to do previous updates, but this Big Sur upgrade seems to need so much spare capacity on what is actually a very limited capacity hard rive.

As I said, I had deleted every deletable app, but there was still not enough space.

So, it's either not possible on this Mac, or it's not possible for my limited expertise.

Either way, I have given up on Big Sur and am currently struggling to restore from previous back-up, which is something I haven't done before on a Mac. I've done it before (years ago) on a Windows laptop and don't recall there being any real difficulties, but on this Mac it doesn't seem straightforward. But then again, it seems that nothing ever is.

Hopefully, when I can get some cash together, I'll get a new machine, as this one just feels very "tired".

I bought my wife a new Windows 10 laptop last year for not much money and everything seems easier on that.

Thanks for trying to help, I appreciate it.

If you have an Apple store nearby perhaps they'd be willing to put it on a flash drive for you?

what emergency patch?

But can you move it back & then Install to that External drive or a new external drive?

👍

Yes, I moved it back onto my MacBook, but it still wouldn't work.

On further reflection, I think my mid-2013 MacBook Air is just too early to accept the upgrade.

Good job I backed up beforehand :)

OK, good luck & take care my friend. :)