Downgrading (user homes) to macOS Sierra
Because of having issues with High Sierra, I had to downgrade to Sierra. My macOS is on an internal SSD (of my Mac Pro) and my user homes are on an external SSD. When downgrading using a backup, Time Machine only replaced macOS (on the internal SSD), but not the user homes (on the external SSD).
Looks like Sierra is not happy with my High Sierra user homes:
Messages hangs
identityservicesd and callservicesd are constantly crashing
my screen turns black, sometimes every few seconds. possibly having to do with the crashes.
Essentially the same problems like in this thread (which is locked): https://discussions.apple.com/thread/8105075
The user of the post above said he could solve his issues with a reinstall of Sierra (which I cannot do and I am also not convinced this changes anything) plus “restoring files by hand from my time machine backup drive with rsync and other command-line tools”. Any idea how to do this or which files need replacement? Deleting ~/Library/Caches did not help. I also restored these with Time Machine which also did not help:
~/Library/Messages~/Library/Preferences/com.apple.identityservicesd.plist~/Library/Preferences/com.apple.TelephonyUtilities.plist
Any other idea?
Some detail on the crashes:
Process: identityservicesd [803]
Path: /System/Library/PrivateFrameworks/IDS.framework/identityservicesd.app/Contents/MacOS/identityservicesd
Identifier: identityservicesd
Version: 10.0 (1000)
Code Type: X86-64 (Native)
Parent Process: ??? [1]
Responsible: identityservicesd [803]
User ID: 501
Date/Time: 2018-02-01 10:00:56.010 +0100
OS Version: Mac OS X 10.12.6 (16G1212)
Report Version: 12
Anonymous UUID: F9C97F8F-70BD-CA59-5E14-105C64D05D82
Time Awake Since Boot: 57 seconds
System Integrity Protection: enabled
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note: EXC_CORPSE_NOTIFY
Application Specific Information:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFData count]: unrecognized selector sent to instance 0x7fa61a012200'
terminating with uncaught exception of type NSException
abort() called
and
Process: callservicesd [996]
Path: /System/Library/PrivateFrameworks/TelephonyUtilities.framework/callservicesd
Identifier: callservicesd
Version: 1.0 (1.0)
Code Type: X86-64 (Native)
Parent Process: ??? [1]
Responsible: callservicesd [996]
User ID: 501
Date/Time: 2018-02-01 10:09:25.222 +0100
OS Version: Mac OS X 10.12.6 (16G1212)
Report Version: 12
Anonymous UUID: F9C97F8F-70BD-CA59-5E14-105C64D05D82
Time Awake Since Boot: 560 seconds
System Integrity Protection: enabled
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note: EXC_CORPSE_NOTIFY
Application Specific Information:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFData count]: unrecognized selector sent to instance 0x7fd24b86e800'
terminating with uncaught exception of type NSException
abort() called
Update: Trying to restore ~/Library/Preferences completely with Time Machine essentially resulted in a deletion. Now the problems are gone but my preferences are also gone. Luckily I have copied the folder before doing so. Thus if I knew which of the preferences needed replacement by the Sierra ones I could restore the rest by hand. Any idea?
It will be very difficult to isolate the issue to individual preference files, since there could be several subtle issues.
Better to take the opposite approach - start with no preferences and only copy the old preferences over one by one as you come across them. That is, as you discover that you have a preference that needs updating, find the single preference file that will give you that preference, and restore it. Re-test and only proceed if things are still stable. Will be a drawn out process, but necessarily so I think. When you can no longer add individual preferences, consider the restoration finished and many set the remaining preferences.
This complex relationship between the OS, Applications and user files is why Apple created Migration Assistant. It might not be help here but it is useful to know just how intricate the process is of "migrating" from one OS version to another.
I am going to go out on limb and say that Apple never intended users to downgrade an OS in place like you’re attempting. You’re basically being your own test pilot which could be seen as either very brave or very foolish. I would suggest that what you’re attempting is not only more trouble than it’s worth, you may never get the results you desire. That’s because even if you could resolve this particular problem it’s more than likely you’re going to encounter something else that blows up in your face eventually. Similarly as others have suggested, assuming you have alternate storage, copy your files and your Library directory from your homedir and start with a clean install of Sierra. Reinstall your apps, use time machine to snapshot the system, and then attempt to restore various settings by manually copying the respective plist files for apps that the you are confident are reverse compatible and making new backups of your system up along the way. If you wind up hosing things with your manual recombobulation of your system, just restore to the last known good state and try try again. If you cannot get the system stable enough to copy your files, use a bootable thumb drive like an installer which can be built following one of the many guides on creating installation thumb drives. Once booted, open a terminal window, attach the external storage, mounted it, and rsync your files. Probably not what you were hoping for, but I think cutting your losses and not succumbing to the sunk-cost fallacy will end up saving you time. Good luck!