what os is supported on a mid 2012 MacBook pro?

Always a good idea >>

Do you have a Rescue Plan In-Place. This comprises having 3 Backups using 2 methods and 1 Off Site incase of Theft, Loss or Natural Disasters. A Time Machine Backup  is very useful and can be used to Revert to Previous Working macOS. For addition purposes - two Tested Bootable Clones each to separate external drives. This is insurance incase the upgrades goes sideways. At least one Tested Clone and / or Time Machine Backup should be Off - Site

1. Lion through Catalina.

2. Yes.

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Armed with that information from previous posting >>

The Age of this computer will Govern what newer version of macOS it will Qualify to install. Use About this Mac from the Apple Icon on Desktop - the required Information will be there.

With the above information in-hand - follow this How to get old versions of macOS and verify what version this computer Qualifies to install.  For Best results use Safari to commence the download as Others may not work.

Make Time Machine Backup  is very useful and can be used to Revert to Previous Working macOS

Notation - Mojave is the Last version to support 32 bit applications / extensions and Drivers. Catalina & Big Sur supports only 64 bit and there is no workaround.

Suggest using Go64 to find 32 bit application before attempting the upGrade. Some or many of the Application already installed may required update or upGrades to 64 Bit Versions.

Are there any AntiVirus, Disk Cleaner, Optimizers, Un-installers, etc installed which should be removed as per Developers Instructions. They are useless, unneeded, cause havoc and interfere with the normal operation of the OS and may even Corrupt the OS requiring a Reinstallation

32 bit apps will not work with Catalina. Download and run the free app GO64 It will show which apps are 32 bit apps and will not work with Catalina.

For those 32 bit apps you'll have to get upgrades from the developers or find an alternative.

This is all good information, thank you. Thanks for the reminder on disk cleaners and uninstall tools, I didn’t consider those.

I always do full backups before and after in case anything goes sideways.

MacBook Pro mid 2012 supports operating system up to macOS Catalina.

Click here; in addition, you should back your data up before upgrading.

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