Questions about upgrading iMAC from High Sierra to Mojave

Topic

New Reply

Sometime in the next few weeks – before Big Sur comes out and High Sierra is no longer supported – I’ll be upgrading an iMAC from High Sierra to Mojave. There are some 32 bit programs on this machine that I don’t think Catalina or higher will run, and I’ve also not been terribly impressed with what I’ve heard about Catalina.

When I open the Launchpad I see an icon entitled ‘Install macOS Mojave’. I’m assuming that clicking on this is an easy way to install Mojave. But, the icon has been there for at least several months (I’m not the primary user of this computer, all I do is keep it updated), so I’m wondering if I’ll get the latest version of Mojave, or if you will, the latest up-to-date version of it?

I’m assuming that at least in principle all the current programs and printers will get carried over to the new Mojave installation? The only other major macOS upgrade I’ve ever done was on this computer going from Sierra to High Sierra. I did that when the machine was only a month old and hardly any programs and no printers had been installed. The current major user of this computer is highly reliant on two installed printers and a bunch (maybe 20 to 30?) of programs.

I’ve read a bit on the Apple support site about upgrading to Mojave and to Catalina, and they suggest starting the upgrade in the evening so that it can run overnight if it needs to!! That seems like a very long time and although the internet connection and electrical power is pretty stable, it’s certainly within the realm of possibility that either or both could fail even if only very briefly. I think it took about 1.5 hours to upgrade from Sierra to High Sierra and a typical ‘point-update’ takes about an hour. Am I really looking at an overnight upgrade?

At the moment those are my main questions. I will, of course, have a backup from Time Machine before I start anything. I’d appreciate any comments/suggestions/answers to my question that anyone has, as well as things I need to pay attention to.

For some reason, I’m somewhat apprehensive about this upgrade, primarily because it would be a real hassle to reinstall printers, browsers, antivirus, and other programs.

Thanks for your help.

Reply | Quote

Replies

DrBonzo, I can tell you just one thing for sure that may be relevant to your situation: I upgraded without any problems from “Sierra” to “Mojave” (skipping “High Sierra”), when “Mojave” was still the latest version of macOS and so being offered in “System Preferences/Software Updates” (with the icon that looks like grey gears). Now you’ll have to get it from elsewhere. Once you figure out where and unless you have to download it from a very slow server and, or  have a very slow Internet connection and a very slow Mac, you’ll probably need considerably less than one hour to get the new version installed. It took me some forty minutes, directly from Apple, if memory serves.

Now for some heavier guessing: If the version you have downloaded and installed is not fully patched, you might find that the “Software Updates” icon on the Dock (assuming you have pinned it there) will show the usual red spot, indicating updates are available. Clicking on this icon, will get you the message that “Catalina” is waiting to install, but if you click on the little tab just below that message, you might get lucky and find that at least the latest patch for “Mojave” is waiting to be installed and also a button of sorts to proceed to install it. This patch has the same number: “2020-004” as the latest one for High Sierra. Beyond this point, my tiny Mac wisdom falters utterly.

Ex-Windows user (Win. 98, XP, 7); since mid-2017 using also macOS. Presently on Monterey 12.15 & sometimes running also Linux (Mint).

MacBook Pro circa mid-2015, 15" display, with 16GB 1600 GHz DDR3 RAM, 1 TB SSD, a Haswell architecture Intel CPU with 4 Cores and 8 Threads model i7-4870HQ @ 2.50GHz.
Intel Iris Pro GPU with Built-in Bus, VRAM 1.5 GB, Display 2880 x 1800 Retina, 24-Bit color.
macOS Monterey; browsers: Waterfox "Current", Vivaldi and (now and then) Chrome; security apps. Intego AV

2 users thanked author for this post.

Nathan Parker, DrBonzo

Reply | Quote

Oh, I almost forgot: I did not have to reinstall any drivers, etc. My peripherals: thumb drive, external Hard drives (including “Time Machine”), the large monitor I sometimes attach to the MacBook Pro, all worked just fine after the install, as did the printer. All the software I had installed with “Sierra”, ditto. But you might have things on your iMac I didn’t have, so cannot be 100% sure you’ll be also completely OK. Maybe 85% sure?

Ex-Windows user (Win. 98, XP, 7); since mid-2017 using also macOS. Presently on Monterey 12.15 & sometimes running also Linux (Mint).

MacBook Pro circa mid-2015, 15" display, with 16GB 1600 GHz DDR3 RAM, 1 TB SSD, a Haswell architecture Intel CPU with 4 Cores and 8 Threads model i7-4870HQ @ 2.50GHz.
Intel Iris Pro GPU with Built-in Bus, VRAM 1.5 GB, Display 2880 x 1800 Retina, 24-Bit color.
macOS Monterey; browsers: Waterfox "Current", Vivaldi and (now and then) Chrome; security apps. Intego AV

2 users thanked author for this post.

Nathan Parker, DrBonzo

Reply | Quote

I had no problems when I upgraded three computers in our household from High Sierra to Mojave. As you probably know, Mojave is the last Apple OS that will support 32-bit programs, so moving to Catalina could be a very different story.

2 users thanked author for this post.

Nathan Parker, DrBonzo

Reply | Quote

Yep, that’s why I’m only going to Mojave right now. The user of this computer has told me the 32 bit programs are in the process of being converted to 64 bit. I’m hoping that will be done in the next few months. My current plan is to get a year out of Mojave and then skip over Catalina to either Big Sur or whatever the newest OS version is at the time.

1 user thanked author for this post.

Nathan Parker

Reply | Quote

Here are the answers to your questions:

1. The Install macOS Mojave App will upgrade your Mac to Mojave. Just click it, run the install, and you’re on Mojave.
2. It may put you on the latest version of Mojave. If it doesn’t, open System Preferences, click Software Update, and download any updates for Mojave (but if it asks you to upgrade to Catalina, just skip it).
3. A Time Machine backup is good to have just in case you need it.
4. Everything will upgrade in place, and nothing should break.
5. If you need to see what apps on your Mac are still 32 Bit, open System Information, go to Applications, then you’ll see a 64 Bit Column that’ll tell you yes or no. You will want your apps updated to 64 Bit before you eventually go for Catalina or later.

Nathan Parker

1 user thanked author for this post.

DrBonzo

Reply | Quote

Sounds good. Back in my Windows days I tried upgrading from XP to Vista and also from Vista to 7. Both times were extremely frustrating and took about a week before I managed to get programs working/downloaded and printers functioning and even then the computers just never seemed the same. So that’s also contributing to my apprehension about upgrading.

I am curious about 2 things:

1) Realistically, am I looking at an upgrade taking overnight, as some of the Apple support pages have indicated?

2) If I recall correctly you have a High Sierra Mac, and I’m wondering if you plan to upgrade to a newer OS.

Thanks for your help.

Reply | Quote

Thank you Nathan. After hours of mucking about a straight shooting answer solves my nights annoyance!!

Your a good egg.

1 user thanked author for this post.

Nathan Parker

Reply | Quote

If the file is already downloaded, it’ll generally be quicker than overnight. The overnight part would be if you need to download the large file. If it’s already downloaded, it could take between 30 minutes to an hour to install.

I have two Macs: old iMac is stuck on High Sierra (can’t go further) and a new iMac Pro. iMac Pro is currently on Catalina. I have successfully upgraded it from High Sierra (what it shipped with) to Mojave to Catalina. There have always been a few quirks with each upgrade (more so with Catalina), but overall my upgrades aren’t too horrible of experiences.

Nathan Parker

2 users thanked author for this post.

OscarCP, DrBonzo

Reply | Quote

When I right click on the ‘Install macOS Mojave’ icon under Properties it says it’s 6.08 GB, so I’m assuming it’s already been downloaded, with only the installation itself left to perform.

I hate throwing away (recycling) old computers, so on the 2 windows machines I mentioned above, I eventually trashed Windows and installed Linux Mint and Ubuntu. Even though the newest of the 2 is 11 years old, they would both be good enough as daily drivers. Maybe you could install Linux on your old iMac.

Reply | Quote

DrBonzo: ” Maybe you could install Linux on your old iMac.”

This is an intriguing twist on the topic under consideration of upgrading macOS: can we “upgrade” our Macs to Linux rather than to Catalina, now, or to Big Sur, later on? With Linux running on bare metal, not in virtualized form? I realized that this is a good thing to know about. So it seemed worth investigating and a Web search quickly gave me the answer: “Yes, We Can!”

It looks like we can either turn a Mac into a 100% Linux machine by installing it and wiping out macOS entirely, or keep both macOS and Linux in dual boot. The first URL below is that of a 4 year old Web page; the second page is maybe a year old or less. A very quick look through each of them did not reveal any obvious contradictions, so looking at both in turn might make things clearer and more informative than looking at just one of them:

https://www.macworld.co.uk/how-to/mac/how-install-linux-on-mac-3637265/

https://www.hellotech.com/guide/for/how-to-install-linux-on-mac

Ex-Windows user (Win. 98, XP, 7); since mid-2017 using also macOS. Presently on Monterey 12.15 & sometimes running also Linux (Mint).

MacBook Pro circa mid-2015, 15" display, with 16GB 1600 GHz DDR3 RAM, 1 TB SSD, a Haswell architecture Intel CPU with 4 Cores and 8 Threads model i7-4870HQ @ 2.50GHz.
Intel Iris Pro GPU with Built-in Bus, VRAM 1.5 GB, Display 2880 x 1800 Retina, 24-Bit color.
macOS Monterey; browsers: Waterfox "Current", Vivaldi and (now and then) Chrome; security apps. Intego AV

2 users thanked author for this post.

Nathan Parker, DrBonzo

Reply | Quote

I do have Linux on it in a VM. I could attempt a dual boot or pure Linux install if need be.

I actually have a use for my High Sierra Mac. It is running some server stuff in VMs, plus I keep a mail client running SpamSieve on it for a spam filtering server. I also keep media on it I can stream to Apple TV as a media server. I’m also running legacy apps on it I can’t run on Catalina (it can still run 32 Bit apps and older Apple apps no longer supported).

So even though it’s “outdated”, I’m not tossing it. I’m still getting plenty of use out of it.

I even recently dragged out my old 12″ PowerBook from 2006. I managed to get a modern web browser on it and enough apps running on it where I could get decent work done on it. If I needed to, I could probably find a PowerPC build of Linux as well.

So even with these old machines, I’m still getting use out of them, and at times, it’s fun to take trips down memory lane with using some of these apps.

Nathan Parker

1 user thanked author for this post.

DrBonzo

Reply | Quote

Interesting. I didn’t know one could do so much with an outdated computer.

1 user thanked author for this post.

Nathan Parker

Reply | Quote

Yep, I’ve found ways to really make old Macs last a long time.

Nathan Parker

Reply | Quote

Nathan: “Yep, I’ve found ways to really make old Macs last a long time.”

Not only the hardware. I have noticed that some colleagues that have been using Macs to do their work for a long time, tend to keep using the same macOS for quite a while after it is no longer supported, for a number of reasons, but manly because they need to keep using software they have developed for those machines, plus other they have installed there, from other developers, that may not be easily (or at all) ported to a newer OS. I am inclined to think that, if everything still works and users are cautious, for most people there is no compelling reason to upgrade the operating system right away and there maybe be good reasons to delay doing that. Although, eventually, one would need to update, or keep the computer permanently off line for doing things that can only be done with the old OS. When that point is reached, the way forward for everything else is to get a new or a refurbished Mac running the latest version of macOS.

An alternative might be to install the old version of macOS and the software that runs well with it in a virtual machine. Is this actually feasible?

Ex-Windows user (Win. 98, XP, 7); since mid-2017 using also macOS. Presently on Monterey 12.15 & sometimes running also Linux (Mint).

MacBook Pro circa mid-2015, 15" display, with 16GB 1600 GHz DDR3 RAM, 1 TB SSD, a Haswell architecture Intel CPU with 4 Cores and 8 Threads model i7-4870HQ @ 2.50GHz.
Intel Iris Pro GPU with Built-in Bus, VRAM 1.5 GB, Display 2880 x 1800 Retina, 24-Bit color.
macOS Monterey; browsers: Waterfox "Current", Vivaldi and (now and then) Chrome; security apps. Intego AV

1 user thanked author for this post.

Nathan Parker

Reply | Quote

What I do for the old machines is put them on a separate VLAN on my network. That way if I need to do something online with them, I can but keep their IP traffic separated from the rest of my network. Even on old machines, I have been able to find decent AV and firewall protection that’s still current.

Nathan Parker

Reply | Quote

I wonder how much of what we have discussed here will still apply when our Macs have ARM CPUs.

Ex-Windows user (Win. 98, XP, 7); since mid-2017 using also macOS. Presently on Monterey 12.15 & sometimes running also Linux (Mint).

MacBook Pro circa mid-2015, 15" display, with 16GB 1600 GHz DDR3 RAM, 1 TB SSD, a Haswell architecture Intel CPU with 4 Cores and 8 Threads model i7-4870HQ @ 2.50GHz.
Intel Iris Pro GPU with Built-in Bus, VRAM 1.5 GB, Display 2880 x 1800 Retina, 24-Bit color.
macOS Monterey; browsers: Waterfox "Current", Vivaldi and (now and then) Chrome; security apps. Intego AV

1 user thanked author for this post.

Nathan Parker

Reply | Quote

Here’s an update as to how my upgrade experience went that might be useful for those of you who want to update from High Sierra to Mojave.

Short version: I don’t think you can do it.

I had “install macOS Mojave” installed on an iMac. Started it from the Launchpad and got a message saying the file was corrupt or damaged and could not be opened or used to install Mojave. Annoying, but thought I’d download from the App Store. No dice. Found a link in an Apple support document describing how to upgrade from High Sierra to Mojave to download Mojave (App Store but a different link). No dice. Tried the same with Safari (used Firefox the first time). YES, got the download, but only after trashing the first “install macOS Mojave” file from the computer. Tried to open the newly downloaded file. NO DICE. Got the same message as before. Maybe a bad internet connection, so tried again (after trashing the previous successful download). No dice. Verified I had a good internet connection on the iMac and on another macbook Air, and on a Linux Mint PC and on a Win 8.1 PC. Everything was fine connection wise. Tried to download again. Same thing – no dice.

So I’m really vexed with Apple by this time. Gave up and just went with Catalina. 40 minute download, then 1.5 hour installation/upgrade. Everything seems to work, although I’m not the major user of the computer. Oh, and there’s a really annoying set of windows that show when you first start Catalina.

The whole reason for attempting the upgrade to Mojave was to get another year for 32 bit support. Fortunately I’ve got a macBook Air running Mojave, and some of the 32 bit programs will run on Win 7 so I’ve got a temporary work around. But…

…Come on Apple, if you say you support Mojave for 3 years then support it for 3 years and make it reasonably easy for your customers to get and use it. I expect this kind of nonsense from MS, not Apple. In return for the premium prices you charge, you should be making my attempted upgrade easy. I understand you want everyone on the latest macOS, but if it’s that important to you then just admit that and tell people you’re not supporting anything other than the newest macOS.

Moderators: delete the rant in the last paragraph if you want, but the rest of the info could be of use to folks in a similar situation.

Reply | Quote

Hard to say, given that you haven’t really provided any information, but it’s possible you’re dealing with an iMac which isn’t capable of running anything newer than High Sierra.  If you’ll click the Apple icon in the upper left and then click on About This Mac, you’ll see a popup displaying some basic information about the machine.  One of the lines has the year the hardware was first released.  With that, you should be able to find information on the machine at EveryMac.com.  If the machine was made before 2013, you’ll have to use the All Years link.  It should spell out what OS the machine originally shipped with, and the highest release it can currently run.

As far as I know, Apple doesn’t have a published policy regarding how long a given OS release is supported with security updates.  But, it’s well known that they support each release for 3 years, after which you’re expected to upgrade to a supported release if the hardware is capable of running a supported release.  They don’t support every bit of hardware they ever made in perpetuity.

It’s possible to run newer releases of macOS on unsupported hardware, but I wouldn’t recommend that for someone else’s computer.

 

Reply | Quote

Purchased on October 1, 2017, brand spanking new with Sierra OS. And, yes, the line to which you refer states the hardware was first released in 2017. So the hardware is fully capable of handling Mojave, and as you already read, I installed Catalina on it after the Mojave installation failure.

I’ve done some very brief investigation since last night (when I did all this) and some folks seem to think there’s some sort of certificate error associated with the Mojave file.

Reply | Quote

No, sorry, I missed that you had installed Catalina.  Good luck to you.

Reply | Quote

It should still be possible to upgrade to Mojave. Here are Apple’s instructions and the download file to it:

https://support.apple.com/en-us/HT210190

Nathan Parker

1 user thanked author for this post.

DrBonzo

Reply | Quote

Yes, that article is the one I found containing the link to the Mojave download (Get macOS Mojave in Step 4). But the link doesn’t work in Firefox, apparently only works in Safari, and while the download does in fact happen, when you open the file it tells you there’s something wrong with the file and that it can’t be used to install Mojave. At least that’s what happened to me. There does exist the possibility that I did something really stupid, or that I’m missing something totally obvious, but … I kinda don’t think so.

Reply | Quote

Unfortunately, the OP has installed Catalina, and the page you linked to says macOS Mojave won’t install on top of a later version of macOS unless you erase the disk.  That’s not an upgrade or a downgrade, but rather a total replacement, so you’d need to backup and restore user data and (at least some) apps.  Doable, but not as straightforward as upgrading High Sierra to Mojave.

Reply | Quote

Sounds like the file might have corrupted, which can occasionally happen with macOS installers.

Nathan Parker

1 user thanked author for this post.

DrBonzo

Reply | Quote

For what is worth: in June 2017 I bought my MacBook Pro with a 15″ Retina display introduced in mid 2015 (before Apple got rid of Ethernet and HDMI and (most) USB ports and moved to all dongles all the time — and butterfly keyboards.) It came with “Sierra.” I skipped “High Sierra” and went directly to “Mojave” several months after the later come out and had no problems at all doing that or using “Mojave” afterwards. None of my browser, etc. settings I still needed were lost.

Ex-Windows user (Win. 98, XP, 7); since mid-2017 using also macOS. Presently on Monterey 12.15 & sometimes running also Linux (Mint).

MacBook Pro circa mid-2015, 15" display, with 16GB 1600 GHz DDR3 RAM, 1 TB SSD, a Haswell architecture Intel CPU with 4 Cores and 8 Threads model i7-4870HQ @ 2.50GHz.
Intel Iris Pro GPU with Built-in Bus, VRAM 1.5 GB, Display 2880 x 1800 Retina, 24-Bit color.
macOS Monterey; browsers: Waterfox "Current", Vivaldi and (now and then) Chrome; security apps. Intego AV

2 users thanked author for this post.

Nathan Parker, DrBonzo

Reply | Quote

Well, I can’t complain about the upgrade to Catalina from High Sierra, per se, it’s just that I didn’t want Catalina, I wanted Mojave. The upgrade itself went smoothly, and it seems that all programs, files, browsers and their settings, printers, etc. carried over from High Sierra to Catalina. It took about 1 hour 40 minutes from the time installation started to when I was asked for a login password. Seems a bit slow to me, but I don’t have much experience with upgrades, so maybe it’s not. Security updates for High Sierra usually took about 40 to 50 minutes.

I’ve done a bit of research into my issues and it does seem as though some folks have had exactly the same issues I did. Some seem to think it’s a problem with faulty and/or outdated certificates.

Thanks to everyone who posted here. I appreciate all the comments, suggestions, and question answers

1 user thanked author for this post.

Nathan Parker

Reply | Quote

If I recall correctly, macOS installers are signed to expire after a certain date. That means if you download the installer for a version of macOS and squirrel it away for several months, the certificate may expire by the time you decide to install it.

The solution, from what I’ve heard, is to do the following:

1. Disconnect from the Internet. Unplug all ethernet cables and disconnect from Wi-Fi.
2. Open the Terminal app
3. To install Yosemite or El Capitan, type date 010101012015. To install Sierra, High Sierra, Mojave, or Catalina, type date 010101012018. Press Enter.

You should then be able to continue with the installation. What this does is changes your Mac’s date to an earlier date so it thinks the certificate is still valid. Disconnecting from the Internet prevents the Mac from syncing back to the correct time.

I also found this thread that might help, but I’ve not tested it. https://osxdaily.com/2019/10/24/fix-install-macos-application-damaged-cant-be-used-error-mac/

2 users thanked author for this post.

Nathan Parker, DrBonzo

Reply | Quote

ETA: I realize I gave the Terminal command for changing the time. I am fairly certain that changing the system time through System Preferences > Date & Time will work as well, so long as you disconnect the Mac from the Internet before doing so. Additionally, if the above Terminal command doesn’t work, add sudo before it, then type in your password when prompted.

Just wanted to add it in here before a user gets frustrated that my instructions don’t work.

3 users thanked author for this post.

Nathan Parker, OscarCP, DrBonzo

Reply | Quote

I can tell you that the first method in the osxdaily link above didn’t work for me. I did everything that method suggested to no avail. Didn’t try the second method and probably won’t. I’ve decided to stick with Catalina. Thanks for the info, though. I suspect it may come in handy in future.

1 user thanked author for this post.

Nathan Parker

Reply | Quote