My 27" 2017 iMac is slow and faulty after upgrading to Monterey

igorvasiak Said:

"My 27" 2017 iMac is slow and faulty after upgrading to Monterey: Upgrading from High Sierra to Monterey created a few issues on my machine. Turning my computer on takes a long time to get past the loading Apple logo screen, and after that any input mediums like the keyboard and mouse still take a while to become responsive.[...]"

-------

Seems as if something is causing your Mac to lag, after login. So, perform the following...

Troubleshooting Lagging Mac:

A. Try Safe Mode:

In Safe Mode, login items do not run, and corrupt system files(i.e. caches) are intentionally reset as a way to fix issues

1. Boot: in to Safe Mode: [Hold Down: shift key upon boot].
2. Log in: as same user
3. Wait: 30 seconds
4. Restart; your Mac
5. Log in: as same user

B. See if your Hard drive is Failing:

What to Try:

• Verify your Drive: Repair your Disk in Disk Utility - Apple Support
• Go Here: If your Mac Starts Up to an Apple Logo or Progress Bar - Apple Support
• Perform the following in Recovery Mode:

1. Boot: into Recovery Mode. Go Here:  How to Use Safe Mode on your Mac- Apple Support
2. Select: Disk Utility
3. Select: the Drive
4. Click: First Aid button

C. Remove Login Items:

While in Safe Mode, remove all of your Login Items, and then restart the Mac.  Go Here: Change Users & Groups Login Items Preferences on Mac - Apple Support

Hi there!

I'd use another app to verify your disk's health, such as SMART Utility. When using SMART Utility, be sure to verify the health of both the Apple hard disk and SSD.

If SMART Utility doesn't detect any health concerns, I'd recommend you reinstall macOS.

How to reinstall macOS - Apple Support

Be sure you have a Time Machine backup; EtreCheck says you might not.

Jack