Cannot update to OS X 11.5 - update downloads but doesn't update. Stalls saying 15 minutes remaining. MacBook Pro Retina, 15-inch, Mid 2014

If this update is for Big Sur 11.5 - the error message can be misleading. There are factors like poor Wifi connection, slow wifi connection, too many other people downloading at the same time and Apple Severs are overloaded, Software on the computer interfering with the download process, running behind a VPN and or / if via wifi too many Other devices using the wifi at the same time reducing the Bandwidth to you computer. Best Results are via Ethernet Cable to Router

There are several ways to download the Big Sur 11.5 update. 

1 - Connect to Router via Ethernet connection and restart the computer in Safe Mode and then open the Apple Apps Store and get the Full Installer of Big Sur. It will be the 11.5 version and once downloaded run the installer from the Applications folder.

2 - Resart the computer in Recovery Mode ( INTEL Command + r ) and choose Reinstall macOS. It too will download the full Installer and commence the installation. For M1 CPU the Recovery Mode is Here

It will take some time and several pauses will occur - normal. Countdown clock may say 15 minutes but in Real time may be 30 minutes. Same goes for clock at 10 minutes could be 20 minutes in Real time. Eventually , Full Installer will download and a New Application in Applications Folder will present called Install Big Sur. 

MickDJones wrote:

Hi

Successfully loaded Big Sur 11.5.

Had to completely remove Sophos software and then download and install 11.5. Worked without a hitch.

Re-installed Sophos.

That was a mistake. First, there is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This user tip describes what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community.  

There are no known viruses, i.e. self propagating, for Macs.  There are, however, adware and malware which require the user to install although unwittingly most of the time thru sneaky links, etc.   

Anti Virus developers try to group all types as viruses into their ad campaigns of fear.  They do a poor job of the detecting and isolating the adware and malware.  Since there are no viruses these apps use up a lot of system resources searching for what is non-existent and adversely affect system and app performance.

There is one app, Malwarebytes, which was developed by a long time contributor to these forums and a highly respected member of the computer security community, that is desshoigned solely to seek out adware and known malware and remove it.  The free version is more than adequate for most users.  

Also FWIW, unless you're using a true VPN tunnel, such as between you and your employer's or bank's servers, they are useless from a privacy standpoint: Public VPN's are anything but private.  

I would recommend you uninstall Sophos according to the developer's instructions.

You should start your own topic and, after reading the following user tip and restate your question/problem in detail: 

Writing an Effective Apple Support Communities Question - Apple Community

This way we won't get your situation and hardware confused with the OP's situation and hardware.

The best alternative is to not have any anti-virus software on your mac.

There are no viruses that attack the mac so having anti-virus is pointless

anti-virus apps run in the background using up resources for no benefit.

often they will flag up files that are system files that you may be encouraged to

delete, thus compromising your macs efficiency. And as you have noticed they

interfere with the downloading of official Apple software.

Contact the developers of any AV software you have and get full uninstall

instructions.

The same is true for any software that claims to clean and optimise your mac

they just get in the way of the macs own management of itself, again

remove any such software according to the developers uninstall instructions.

Read this,

https://discussions.apple.com/docs/DOC-8841

This happened to me multiple times in getting 11.4, actually, and I kind of just had to wait it out. It crashed multiple times, but it ultimately got there. I've gotten 11.5 downloaded (supposedly), so now I'm in the same boat of just waiting it out again and praying it doesn't crash.

When downloading from Apples servers it is always best to have your mac connected to your router via cable,

WiFi is too unreliable.

Do not use the mac while it is downloading and do not use any other devices while the mac is downloading.

I'm having the same problem on my 2017 iMac 27" - quits downloading macOS 11.5 at exactly the same point: 15 minutes left in download. Even left computer on all night and, when I came back in the morning, the download was still stuck at "15 minutes left" When I restarted the computer this evening and tried to download the update, AGAIN, it stopped with 15 minutes left!

Is there any way to delete whatever has been downloaded so far so that the download won't restart at the point it left off and maybe, if the download process has to start from scratch, it might finally complete?

I tried again and ran the macOS update, but this time I watched as it completed the download, then froze at "15 minutes left" during the "Preparing to Install" phase. It was then I noticed that my free antivirus software was downloading updates. Since I have the free version of this antivirus, I have no control over when it updates, so the only thing I could do was to uninstall it. After doing that, I again tried the macOS update and this time IT WORKED and completely finished downloading, preparing, and installing macOS v.11.5 with NO PROBLEM! So, if you have antivirus software installed, you may want to disable updates or, as in my case, uninstall it and then try the macOS update. Hope this helps!

(Btw, after the macOS update finished installing and my iMac restarted, I re-downloaded the antivirus program but am now looking for a better alternative that will not force me to uninstall every time a new macOS version is available, like the upcoming Monterey.)

Any Third Party Applications that will interfere with the normal operation of the OS, alter, modify, remove or delete or attempt to do so is an invitation for disaster and may require a Reinstallation of the OS. And AntiVirus Software falls into the above Category

There are no known Viruses in the wild that self replicate and affect macOS. There are Malware and Adware that does affect macOS and are often times downloaded as part of an Application from Third Party UnTrusted Site and get installed along with the Application.

Suggest downloading from a Trusted Developer and Respected ASC Contributor the application Malwarebytes for Mac. It is free or paid for added features. Run the Application and it should remove the malware / adware. Once done, restart computer and test.

STEP 1 ::

After downloading the update,  it said "About 15 minutes remaining" ; 

After approximately 15 minutes, it said "About 10 minutes remaining" ,

There after approximately 15 minutes, it said "About 5 minutes remaining" ,

STEP 2 ::

Finally after close to 45 minutes, it asked for a RESTART my MacAir to install the update.

My Air restarted once.

Then after 3 minutes, again restarted.

During the third restart, it said 10 minutes, but approximately took 15 minutes to restart.  

Finally it asked me for my Login Password.

And then after loading the UI completely, it Displayed the message : “Your Mac is up to date — macOS Big Sur 11.5.2”  

Total time :::: 83 minutes (20 minutes to download the update BigSur 11.5.2 plus 45 minutes before restarting

             to update the patch plus 18 minutes to complete the installation).  

a partial Welcome.

As has been pointed out by @Old Toad and self - AV software is eventually going to cause such havoc and may even corrupt the installation requiring a Wipe and Reinstallation.

How do I update my MacBook Air 13 to 11.3?