MacOS Catalina 10.15.5 introduces battery health management in the Energy Saver settings for notebooks, an option to control automatic prominence of video tiles on Group FaceTime calls, and controls to fine-tune the built-in calibration of your Pro Display XDR. The update also improves the stability, reliability, and security of your Mac. I downloaded it from a url, not having it handy. If you can share any drive access, I have the Catalina installer to share. And you can do this by downgrading the macOS to 10.14 Mojave, and then you can use the installer that I have mentioned above. From there on you can use apple downloads to upgrade further versions of Catalina.
macOS 10.15, also known as macOS Catalina, is Mac’s most recent—next-generation—operating system. Apple’s macOS Catalina comes with more to offer compared to its predecessors. A few of this operating system’s features include experience-dedicated apps for podcasts, TV, and music. The best part about this OS is that upgrading is easy and free for all Mac users.
Before getting started, you first have to check if your Mac meets Catalina’s hardware requirements so you can proceed to install it. Here is a list of Mac devices and models compatible with macOS Catalina:
You can follow these steps to find out the kind of Mac you have:
In macOS Catalina, Apple no longer supports any 32-bit apps. Therefore, any apps on your Mac that have not been updated from 32-bit to 64-bit will not function on this OS.
To identify the 32-bit apps on your Mac, follow these steps:
Before you can upgrade to macOS Catalina, there a few things you have to sort out first, such as:
Before upgrading to macOS Catalina, it is crucial to create a Time Machine backup. The reason for the backup is a safety measure for when you find your Mac to be incompatible with the Catalina OS, which means you can erase the upgrade and restore it using the backup you created.
Creating a backup whether upgrading or downgrading your Mac is not only a good idea, but also imperative. Unless you would not mind losing everything, we highly recommend creating a Time Machine backup before upgrading to macOS Catalina. Without the backup, it would take a lot of time to restore your system to its previous OS. You would have to download each program, plug-in, and driver once more.
Follow these steps to format an external hard drive for macOS:
Follow these steps to create a Time Machine backup drive:
The upgrade to the macOS Catalina process involves two steps: backup and installation. After you have created a backup, the next step is visiting the App Store to download the macOS installer. Depending on your internet speed, the download may take some time. Upon completing the download, you can install the macOS Catalina app that you can find in your Applications folder.
macOS Catalina needs storage of 12.5GB to 18GB for upgrading. Therefore, if you have insufficient space on your Mac, you can make a backup of some files then delete them from your system to avail the storage required.
Any older versions of Mac OS X 10.7-10.10 have to first upgrade to Mac OS X El Capitan 10.11 version before upgrading to macOS Catalina, which you can download from Apple’s Catalina download page.
To do this, follow these steps:
Follow these steps to install macOS Catalina:
Follow these steps to complete installing macOS Catalina’s new features:
Customers get Software upgrades for Mac computers through the online app store ever since the release of macOS Lion. Be it a clean install or upgrade, Mac App store require you connect to the internet to download whole installation files. The online OS update is OK if you have stable broadband connectivity and enough bandwidth. Apple also provides an option for internet recovery of macOS if your computer fails to boot. But there are situations where you can’t download the OS from the Apple servers. Having a macOS offline installer or a bootable USB disk is the only solution in such scenarios.
Installing macOS without internet requires a bootable USB disk. And you need to download a full-size macOS installer for making this disk. Hence, before anything, we will tell you how to download macOS offline installer directly from Apple to your Mac using a GitHub script.
Download the gibMacOS script from this link and extract it to your Mac. From the extracted folder, run the script called gibMacOS.command — it will open the Terminal as shown below.
Wait for the script to fetch the macOS download catalogue from Apple. When the list is ready choose a number as per your OS option and press the Return/Enter key. You can use this script to download macOS Big Sur (11.1), Catalina (10.15), Mojave (10.14), and High Sierra (10.13.6). A new folder “macOS downloads” appears in the “gibMacOS-master” as you provide a download option, and the OS starts downloading as you can see in the video.
The OS gets downloaded as parts, PKGs, DMGs and other files. For macOS versions up-to Big Sur, you need to use another script “BuildmacOSInstallApp.command” in the main folder to join all the downloads and make the full macOS installer app. All you need is to drag and drop the downloaded macOS folder to the terminal window. The script will build the offline installer and save it to the same folder.
You don’t need to use the second script if your choice is macOS Big Sur. Because, for macOS Big Sur you get a full-size installer from Apple in PKG format. Double-click and open the InstallAssistant.PKG to save the “Install macOS Big Sur.app” to the Applications folder.
Apart from this, some older versions of macOS are available for direct download from Apple (Sierra, EL Capitan, Yosemite) in DMG format.
It is possible to create a backup macOS installer on a DVD or USB drive but later is the best choice. Most of the Macs these days don’t have DVD slots, and the installation through a disc is very slow. Hence we discuss only about making macOS recovery installer on a USB disc. For this you need a Mac and a USB pen drive of at least 8 GB space, and a third-party app called DiskMaker.
Unfortunately, the above app is not compatible with macOS Big Sur 11 and above. Check the instructions on Apple website, the manual method to make macOS offline USB installer.
What is the alternative if I don’t have usable Mac at the moment?
This method is applicable when you have a Mac, and the internet recovery fails. But think about a situation when your only Mac stops to boot, and you don’t have USB installer or TimeMachine backup! Downloading MacOS DMG file might save you. If you have a macOS DMG, you can create bootable USB disk from a Windows PC — use a software like TransMac for this purpose.
As said earlier, you could use the macOS USB installer to do a clean install or restore it upon a boot failure. Just connect the USB disk and press the Option/Alt Key when you hear the boot sound. The Mac will then display all the startup disks available.
Pick the USB drive starting with the label “Install macOS” and follow on-screen instructions to complete the installation. If you need, use the Disk Utility to format the drive for doing a clean install.