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keith liFlag for Hong Kong

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mac 21.5 inch 2012 imac OS upgrade problem

Dear all, 

               I have a imac 21.5 inch 2012 with lion X OS reloaded, and i'm having difficutly to upgrade the macOS form software update, it shows "an error occurred while downloading the updates", i tried to download X EI Captian 10.11.6 and insert into the usb and hold option button to install macOS manually, but seem not quite working, just wonder my imac is only compabitle with OS X 10.8.5 only ? but by google it some people said i can upgrade to the macOS newer than the one i'm using, any help would be appreicated 

below are the macOS i download and make insert in into the usb 

Download macOS

Create bootable macOS installed via usb


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You should be able to upgrade as recent as Catalina MacOS 10.15.

My go-to resource for Mac upgrades is Other World Computing. Here they list Mac OS compatibility by model.

What browser are you using?  You need to use Safari to actually make those download links properly redirect to the Apple App store to download it.  It won't work through other browsers.

Also, Catalina removes 32 bit support, so I wouldn't update to that if you must use older 32 bit software.  Mojave is the last version that supports 32 bit software.  I created a Mojave VM when I had to upgrade to newer versions.

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actually when I download those dmg I was using other window computer other than the Mac itself, coz when I found that the Mac has difficulty to access internet probably, but it's work for some site but not for the other, may be I will give it another try again, what about if it's doesn't work in this way other alternatives I can get my iMac OS upgraded ?
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my imac connected with ethernet cable and internet connection drops intermittently, and i have another macbook will try to download the Catalina DMG and copy it to the usb thumb and copy it to the imac and run it directly, thanks for your suggestion  
may i ask i can download the dmg directly from app store in other mac ?

You should be able to.  It's just a DMG and you can copy it to any other Mac to update them.

let me give it a try thx for your suggestions
I have downloaded and copy the Catalina to the iMac and install but I'm receiving below, do I need newer version than Catalina ?

you have os x 10.8.5 the application requires os x 10.9 or later

Can you check from when exactly your iMac is? I see is from 2012 but Catalina is only supported from iMac Late 2012. You can check in the Apple menu, about this Mac.

I just downloaded High Sierra from App Store, this is the closest version to 10.8.x available download from Apple, the previous one I couldn't find, at the same time I will check iMac late 2012 compatible to which macOS version thx for yr reply

Any update you can share? Thx. 

I'm out of town these day and will be home after few day to give it a try and let u know status
just wonder if you can provide the full OS version download of
EI Captain and Yosemite ?
i have downloaded EI Captain, and get it installed, below are the steps, and after the installation, its has nothing changes, any idea ?

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It looks like it's installed.  If you mean that the internet is still having problems, then you may be having hardware issues.  Have you tried a different ethernet cable?  Did you try a different port on the router or switch?  Have you tried WiFi?  

>> its has nothing changes

Not sure what you mean by this? Can you elaborate?

Have you restarted and what do you see under 'About this Mac'?

i having difficulty to connected to the internet, its intermediate dropped for internet access, and not about to connect to my home wifi, i used this cable with same port to other computer its has no issue, may be i will try to use a ethernet adapter with usb to give it a try

So the upgrade to El Capitan was successful? 

Did you have problems accessing internet before you asked this question?

I'm just asking because if the upgrade is OK then you would probably need to ask a new question for that. 

Based on how the original comment was worded and his earliest responses, he was having network issues and was reinstalling in hopes of repairing the internet connection.

If you connect your WiFi momentarily to check, you can determine if the problem is just ethernet issues or something greater.  If you don't want the WiFi saved, you can Open Your Network Preferences, select you WiFi, click Advanced and delete you WiFi from your Preferred Networks list.

You can also look inside that ethernet port on the back of your iMac and check to see if there are bent connectors inside.  Also, it wasn't completely clear if you tried a different ethernet cable.  You only mentioned that you used this cable on another computer.

This mac seems old.  Have you tried opening it up to look inside and maybe clear out any dust clogging any vents?  Maybe it's overheating somewhere and just needs some cleaning.

Also, you can run Apple Diagnostics to check your system.  Restart your computer and Press and hold d upon startup.  You can let go when you see the progress bar show up.

thx for your useful information will give it a try and let u know result

Can you let us know why you selected that comment as solution? Thanks.