iMac won't shutdown or restart

[barrygou]

My 6 month old iMac won't shutdown or restart from the Apple menu. I tried resetting the SMC. I have to manually use the power button.

 

[coodem]

Something [process/program] probably stopping it. Open activity monitor before you shut down and see if anything is hanging

 

[barrygou]

I took it to an Apple retail store Genius Bar. They very quickly discovered it was remnants of anti-virus program Kaspersky causing the machine to hangup on Shutdown or Restart. Months ago, I installed a trial version of Kaspersky and decided not to use it. Instead of using the Kaspersky Uninstaller I just dragged it from Applications to Trash. The Apple tech downloaded the trial again and then used the Uninstaller to remove it. Issue solved. Lesson learned. Check to see if an app has an Uninstaller and use it rather than just dragging to the Trash.