iMac Freezing and Rebooting Issues on Mojave – How to Fix

imacmojavewifi

After upgrading my 2015 iMac (Intel i5, 8GB RAM, 1TB Fusion Drive) to Mojave I been having nothing more then headache.

It all started with WiFi randomly dropping and when I navigate to the WiFi menu I'm greeted with spinner of death. With only solution is to restart or to logout, unless the whole system lags out and then you have to physically power it down.

The other issue is partially related to WiFi is that when WiFi drops it seem's to kill whatever Browser is running, at first I though it was Chrome acting up as it's a major RAM hog, but this also seems to happen to Opera but less frequently.

When the Browser crashes you can "Kill Process" but even so you will still have the Browser window overlay everything with no ability to Hide or Close it. Again at this point you can't use Navigation menu's as such you have to physically power it down.

And last issue is that I can be working on something and when I come back I'm greeted by Login screen, because for whatever reason the OS restarted itself. Same seems to happen when I try to use the computer in the morning, the iMac is once again has rebooted somewhere over night. Mind you the iMac runs 24/7 like most of PC's I owned and have.

So what troubleshooting solutions did I partake?

  • Reset SMC on the iMac (Performed this task, no result)
  • Reset NVRAM on the iMac (Performed this task, no result)
  • Check Disk (Performed this task, no result, no errors found)
  • Auto Updates is Disabled and is set to Manual

I will say for the record after random reboots I installed a copy of Windows 10 along the OSX, and guess what I at times come back to Windows 10 booted up. However Windows 10 does not seem to suffer from this Random Reboots, so I'm gonna guess the Reboots are isolated to Mojave.

Any suggestions? At this point I either have to figure how to downgrade or to backup everything and try to do a clean install.

Best Answer

My friend, I noticed something similar with my iMac 14,2 made in 2013. My iMac began to do kernel panics or reboot, denying me use of my machine.

I narrowed the problem down to the wireless, there appears to be a potentially exploitable bug involved, and the solution I have used for some years now is to simply turn off the wireless interface in network systems preferences. This has afforded my the ability to use my machine without problems.

F.