iMac Mid 2011 Continuous Power Off Issue -

Ok, after a couple weeks, this is what's happening:

Every 2nd or 3rd power on the computer will power off and on a couple times. I have stopped bothering with the ctrl/option/P/R routine as this seems to do nothing but make me feel like I'm doing something.

So after this happened the second or so time after the initial .plist file deletion, I rechecked the preferences folder and sure enough, there were new .plist files in there.

It appears as though each time I use the computer, new preferences or .plist files are created. For some reason, one or more of these files will mess with my start up.

After deleting the .plist files again, the problem was solved, again. Until a couple times or the next time when more .plist files needed to be deleted.

I would say that deleting the .plist files is the immediate solution however, the creation of certain .plist files is the true culprit. I need to figure out which file is the problem child and how I can keep if from creating itself.

In the meantime, I try to remember to go into the preferences folder and delete the .plist files before I power off each time. This is a pain, but not as bad as the incessant power off power on cycle that was happening.

This article was interesting. I've looked at my launch apps briefly, but it's a looong list. It may hold the answer to my problem.

https://www.macworld.com/article/2047747/take-control-of-startup-and-login-items.html

Several months ago the graphics card was changed because of a flickering problem. I added more memory at that time too. At that time dust was cleared out. Maybe more has accumulated.

Hi, thanks for the assistance.

I downloaded the etre app. Did the scan and here's the report:

Performance:

    System Load: 1.38 (1 min ago) 1.62 (5 min ago) 1.60 (15 min ago)

    Nominal I/O speed: 4.92 MB/s

    File system: 30.70 seconds

    Write speed: 88 MB/s

    Read speed: 108 MB/s

CPU Usage Snapshot:

    Type Overall

    System 2 %

    User 3 %

    Idle 95 %

Top Processes Snapshot by CPU:

    Process (count) CPU (Source - Location)

    Other processes 21.32 % (?)

    Messages 8.15 % (Apple)

    EtreCheck 4.19 % (App Store)

    suggestd 1.98 % (Apple)

    cloudd 1.86 % (Apple)

Top Processes Snapshot by Memory:

    Process (count) RAM usage (Source - Location)

    EtreCheck 576 MB (App Store)

    Dropbox 329 MB (Dropbox, Inc.)

    Adobe Desktop Service 242 MB (Adobe Systems, Inc.)

    Messages 189 MB (Apple)

    Safari 161 MB (Apple)

Top Processes Snapshot by Network Use:

    Process Input / Output (Source - Location)

    Other processes 334 KB / 757 MB (?)

    Dropbox 116 KB / 144 KB (Dropbox, Inc.)

    SystemUIServer 0 B / 64 B (Apple)

    routined 0 B / 0 B (Apple)

    universalAccessAuthWarn 0 B / 0 B (Apple)

Virtual Memory Information:

    Physical RAM: 16 GB

    Free RAM: 1.19 GB

    Used RAM: 6.02 GB

    Cached files: 8.79 GB

    Available RAM: 9.98 GB

    Swap Used: 0 B

Software Installs (past 30 days):

    Install Date Name (Version)

    2019-12-10 Adobe Flash Player (10.3.183.11)

    2019-12-10 Safari (13.0.4)

    2019-12-13 XProtectPlistConfigData (2110)

    2019-12-13 MRTConfigData (1.51)

    2019-12-29 EtreCheck (5.4.8)

Clean up:

    ~/Library/LaunchAgents/com.adobe.ARM.***.plist

        /Volumes/M*******F/M*********s/A*************p/A**************************l/A****************************p/C******s/M***S/U*****r/A******************************p/C******s/M***S/A**************************r

        Executable not found

    /Library/LaunchAgents/com.canon.MFManager.plist

        /Applications/Canon Utilities/ImageBrowser EX/ExtApp/MFManager.app/Contents/MacOS/MFManager

        Executable not found

    ~/Library/LaunchAgents/com.adobe.ARM.***.plist

        /Volumes/M**2/M*********s/A*************p/A**************************l/A****************************p/C******s/M***S/U*****r/A******************************p/C******s/M***S/A**************************r

        Executable not found

    ~/Library/LaunchAgents/com.adobe.ARM.***.plist

        /Volumes/P***************s/A**********s/A*************p/A**************************l/A****************************p/C******s/M***S/U*****r/A******************************p/C******s/M***S/A**************************r

        Executable not found

This seems to have fixed the problem! The computer shut off once right after I deleted the files. I walked away from the computer to see if it would shut off came back several hours later, the computer had gone to sleep. When I woke it up the computer shut itself off and restarted on its own. But since then, it has stopped the repeated powering off and restart process. Will come back to this conversation if it starts again.

And thank you!!!

( I was considering buying another computer. And not a Mac. But I wasn’t quite ready to snip the umbilical cord to Apple, although I know it’s inevitable given apple’s customer un-friendly marketing model. Their now sealed computers, unable to be upgraded or updated by non-Apple entities, their constant updates and need for larger operating system capacities, and their products that become unsupported and obsolete well before I am able to purchase new it’s really sad given that I like the products so much. But they are advancing well beyond my tax bracket. Sigh...)

Great, I will check that out and get back. Thanks!