dfaulks":1792tgu0 said:
Every time I wake up this iMac, there is a message - or two, or three, or more - which tells me that the disk was not shut down properly.
I thought that one just hooks up an external drive and gets TM operating and all is lovely.
Can't find anything on line that outlines the proper procedure.
First question would be: In Energy Saver under System Preferences, do you have "put hard drives to sleep when possible?" If so, turn that off. Sleeping external drives causes them to dismount. If the machine in question supports "Power Nap" (i.e., it's a recent MacBook model) then keep the "Power Nap feature" turned on.
Second question: do you have any of the manufacturer-supplied "software" for the third-party external drive installed? If so, uninstall it.
Time Machine drives should not sleep, because they dismount themselves first, which is what's giving you the error message. Then Time Machine wakes them up to do the backup, they remount, and repeat the cycle.
Other option would be to dismount all external drives when you are done with the computer as a matter of course. Time Machine will wait until the external drive is remounted before doing another backup, and of course there's really no need for it to do a backup when you're not using the computer, as nothing will have changed.
Finally, there is also a free utility available here
https://tclementdev.com/timemachineeditor/ called Time Machine Editor that allows you to customise when Time Machine runs (if you don't want to dismount the drives for whatever reason).
