2020 iMac running slow and unresponsive on macOS Sequoia 15.7.4

My 2020 iMac is running slower than normal lately and many timed when I click on something nothing happens. I seem to have 272GB of 499 available so doesn't seem like that's slowing it down, any ideas as to what might be causing it. I'm running Sequoia 15.7.4 which I haven't updated as I also have a 2014 iMac that is synced to this one and was told updating it on the newer iMac might affect the older iMac. Thanks in advance for any advice you can offer.

Posted on Nov 10, 2026 4:30 PM

1 reply

MrHoffman

Level 10 (169,253 points)

Nov 10, 2026 5:05 PM in response to iMac4meX2

Here is some info on a common (slow) configuration: Why is my hard disk drive iMac so slow? - Apple Community

Other causes of slowness can include failing storage, add-on security and cleaning apps, VPNs, and other such.

If you don’t have current and complete backups, go get a backup now, before doing anything else. This given the possibility of a nascent hardware problem.

Updating a Mac is unlikely to effect a second and separate Mac.

For this case, please download and run EtreCheck (the free version, don’t need the paid version here), and use the Share to share the results to the Mac clipboard. Then open a new reply here, and press the Additional Text button (the button that looks like a printed page), and paste and post the hardware and software configuration report here. From that, we can get a little more detail about what is installed and what is running here.