I'm having trouble updating my iMac. When I check for updates under 'About this Mac' and then 'Software Update', it doesn't show any available updates—just a message saying 'Incompatible Updates'. I'm currently running macOS High Sierra (Version 10.13.6), and I'm hoping someone can help me figure this out!
2 Answers
It sounds like your iMac is pretty outdated, especially since it's on High Sierra. Most likely, it's not supported for newer macOS updates. If it's an older model, your best bet might be switching to a lightweight Linux distro if you want to keep using it safely and get some form of updates. It'll work much better on older hardware than the latest macOS versions.
First off, can you tell me what model your iMac is? That information can help us understand what's going on. It might be that your iMac is running an older version of macOS that doesn't support updates anymore. Many of the earlier iMacs, especially those from around 2011 or before, are stuck on older OS versions and can’t get the latest updates anymore.

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