macOS Big Sur 11.2 update download failed error

https://discussions.apple.com/docs/DOC-250003367 Read right to the End and within that posting is a Link to Best Defense from Malware etc

Without getting long winded - on these Forums AV Software is considered as ^%$ware and that is based on Very Very Long experience of myself and those even longer on the Apple Eco-System. Viruses do not exist for macOS, yes Malware does but only if people purposely download or do not do due Diligence on where they get their Software

It's not about personal preference. Advices like this (uninstall a whole category of programs _plus_ VPNs) along with the whole restart your system, boot in safe mode etc are what programmers call Shotgun Debugging. There are logs in every system that can help understand the problem (I had it too without having installed any of the "cursed" software mentioned - only thing worked was a recovery reinstall) so Apple Support _had_ to ask for those logs... but they didn't.

Almost afraid to ask- any antivirus software installed?

Extremely probable. Without long store totally unneeded, disrupts the normal operation of the OS and can corrupt the OS. Remove as per Developers instructions asap

It is not the Wifi, the message is misleading.

I tried to install several times in the past few days. Get this message every time, Wifi is working fine everywhere else. Tried with a cable connection instead of Wifi, same result.

Also, I do not have a download in my Downloads folder (~/Downloads). Do not remember seeing a download there for any previous system updates either.

I've been having the same problem since updating to Big Sur. Each update has been difficult, with multiple fails. And it's happened to three other Macbooks in the house. I second the thought that there should be a method of downloading once rather than re-downloading the same file over and over again. Moreover, once for the entire household would be even better. What a waste, especially for people on limited connections. In any case, I've tried everything except re-installing and would prefer not to lose the day it will take to do so. This is a pretty offensive suggestion for a $2trillion company: "If the issue persists, try reinstalling the current software using macOS Recovery and then downloading the update again." Waste your time, not ours! Have a good day! Seriously. Fix your software.

As I said, I have already upgraded to Big Sur (which involved at least 10 separate 12+gb downloads!). I am trying to install one of the frequent updates to Big Sur (which has now involved a similar number of 2+gb downloads). Does the same hack work for updates? This seems pretty silly, frankly. In any case, each time I attempt to update, whether in safe mode or not, the download completes and then freezes with a message that 10 minutes remain. I have left it in that state, with the fan on constantly, over night. Also, one process is usually pegged at high CPU usage. I can't afford the time or bandwidth to do this again right now, but here's a screenshot of the beginning of the name of the process (com.apple.MobileSoftwareUpdate...)

Those using this ^&*ware are somewhat misguided. macOS is not Windoze environment. Carrying that idea over to macOS is a big mistake. As many persons, on this thread, may have AV, Disk Cleaners etc installed - even disabling said stuff and still having issues installing the Big Sur update tends to prove the point just how invasive and disruptive this is.

The advise offered to intending to assist. The User always has the choice to accept it or disregard it.

I have the same problem with a 1 ½ year old iMac 21.5 in Retina with 3.6 GH i3 and 16 GB ram and 1T hard drive when I tried to update to both 11.2.2 and 11.2.3. And yes I turned off my Norton anti-virus and same message pops up after the update has already been downloaded and it is ¾ of the way through the installation. Reminds me of a Windows 7 update that permanently rendered 10's of 1000's of machines unable to ever do an update again: had to bin it and buy a new windows machine with that one. Come-on Apple give your customers the support they deserve: they are paying your salaries after all. Please fix this Big Sur garbage and don't abandon us.

OK, I have tried the following:

1) Connected to modem by ethernet cable.

2) Re-booted modem.

3) Un-installed Norton Anti-virus software.

4) Performed Disk First Aid on HD in Recovery mode.

5) Activated Contact Cacheing with "all content" unlimited.

6) Tried the download in Safe mode.

All of these have failed repetitively.

With Activity Monitor, you can see that the actual download finishes but then as the install proceeds, it gets to between 10GB and 14GB of reading and then it suddenly stops and gives that same "download failed, check your internet connection."

Obviously, this has nothing to do with the download failing and there internet, it is Big Sur itself that is halting the process.

This is so incredibly frustrating to be given advice that leads one on a wild goose-chase and yet the problem remains.

Does anyone in support actually look at code to see if there is an obvious problem there?

I tried again in safe mode and got the same failure again around the 10GB reading point after the apparently successful writing portion of the download. I managed to get a system_logs.logachive which looks like it has details of the failure. How do I upload this to support or to the powers that be?

This is the first I've ever seen of this. Can you provide links to support this claim?

Okay, but I already tried installing in Safe Mode, which ought to mean no ESET. So...I've already tried and it responds as above (hangs with "10 minutes remaining"

Also, “extremely probable”?? Why? The link posted includes VPNs to “unnecessary” software. Go figure...

Thanks Vakoinoglou, I have uploaded a systems log with the issue via the Feedback Assistant App as you suggested. Hopefully someone will notice and take an interest in it.