What's the best macOS for a 2015 iMac?
I'm running a late 2015 iMac - 4 GHz Quad-Core Intel Core i7 on Monterey 12.6.9. I am having problems with my finder search function. I type one letter and I get the spinning disk of gloom. If I wait several minutes for it to stop, the results list is blank. Same thing if I search for an email in Mail. I've tried the plist fix and re-installing the OS. Am I running a OS that is too advanced for my iMac? Any idea how I can fix my search problems? I called Apple support and they said they don't support iMac this old. Referred me to a 3rd party, which I don't know how good any of them are. I would rather fix myself. I have a time machine disk going all the way to 2020. Help.
iMac 27″, macOS 12.6