Doing everything possible to make this problem go away. I got a 36 hour reprive by deleting the aforementioned plist files.
The only way I've found to make the change permanent is to power off the computer, and never turn it on again!
You'll notice that when the problem comes back, so does that .plist file.
Macintosh HD/Library/Preferences/com.apple.preferences.sharing.plist
Again, Onyx shows that file as corrupt.
Enabling any of the "Services" under "Sharing" is clearly the source of the problem.
Note: I'm testing this on two computers. The second computer has not yet recreated the .plist file and is not having the problem. I'm betting that it will recreate the .plist and the problem will come back.
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I believe that I have solved the issue here on my MBP.
Things I did:
Deleted these files:
Macintosh HD/Library/Preferences/com.apple.preferences.sharing.plist
Macintosh HD > Library > Preferences > SystemConfiguration
com.apple.airport.preferences.plist
NetworkInterfaces.plist
preferences.plist
Toggled "Find my Mac" multiple times in the iCloud pref pane and each time went back to the Sharing Preference and removed the appending numbers.
Unplugged my Airport Extreme and restarted my computer.
Let the computer restart and then plugged the AE back in.
I did note that when I toggled the "Find my Mac" in the iCloud preference pane that it would complain that I had "Wake for network access" turned off. But the thing is, I didn't have it turned off. Toggling that off and on didn't make any difference. Whenever I chose "Find my Mac" it said that Wake for network access was turned off (it wasn't). This confirmed for me that my preference files were screwed up.
After tossing the pref files and restarting, I could toggle the Find my Mac and it would accurately assess that the Wake for network access was checked.
Note that for me "Wake for network access" is enabled and the problem has disappeared for me.
Finally, for good measure, I restarted the computer with Command-R and erased my hard drive, reinstalled Yosemite and restored my computer from a Time Machine Backup. When I restored I did not choose to reimport my computer and network settings.
So far so good!!!
Let us know if the ".plist" file comes back with the problem. That's what happened to me. So far shutting off all of the services seems to be the only solution that works for me.
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Yes, I have this problem with a fresh install.
I have "fixed" it with disable 'Wake for network access'
After the fresh install did you import your account(s) using Time Machine or any other method that would bring your preference files on to the fresh install?
What I'm wondering is if anyone is having this problem with a fresh install that did not restore the preference files.