Sierra - Help, I am not impressed

I have just updated my iMac 27 inch late 2013 to Sierra and now every time I use the machine after it has gone to sleep I get the message that the Disk was not ejected properly.

I have 3 USB external disks that have been working perfectly well on OS X 10.11 but this problem started as soon as I updated to Sierra.

I have tried everything possible that has been suggested on various forums but nothing has worked.

I last had this problem with os X 10.9 (I think) which was fixed by one of the updates. Now it is back!

Please help. It is driving me mad!

Edited by deleted (Wed 02-Nov-16 17:52:02)

http://forums.macrumors.com/threads/disk-not-ejected...

Try post no 40, I know it's el cap but may work.

Thank you Stniuk.

I reinstalled Sierra and then plugged all the drives directly to the back of the iMac. So far so good but will be keeping a close eye.

Actually, I'm quite impressed. My even more aged (late 2009) 27" iMac is performing even better on Sierra 10.12.1

It seems to have had a new lease of life.

I agree. Things like Time Machine back-up to my Synology RackStation and syncing to iPhones and iPads have suddenly starting to work properly which they have not done for some time. I was thinking of replacing my iMac but perhaps I can delay that now