Apologies in advance if it's inappropriate to post log output.
I will remove if it is a problem.
I'm also having the same issue on my 5K iMac. Random Reboots sometime multiple times a day. Occurring after updated to 10.11.4
I've clear PRAM and SMC.
I have also reinstalled OS X. Complete reinstall erased drive.
Issue still persists.
-128 SHUTDOWN CODE
Here is some output regarding how frequently the reboot occur:
last reboot
reboot ~ Wed Mar 30 18:24
reboot ~ Tue Mar 29 22:45
reboot ~ Tue Mar 29 20:06
reboot ~ Tue Mar 29 09:30
reboot ~ Mon Mar 28 23:00
reboot ~ Mon Mar 28 12:11
reboot ~ Sun Mar 27 19:10
reboot ~ Sun Mar 27 09:20
reboot ~ Sat Mar 26 19:39
reboot ~ Sat Mar 26 10:13
reboot ~ Sat Mar 26 09:44
I've looked through console can't pinpoint an exact cause.
At first this error was corresponding right before each reboot:
CalendarAgent[413]: [com.apple.calendar.store.log.caldav.coredav] [Refusing to parse response to PROPPATCH because of content-type: [text/plain; charset="utf-8"].]
I removed all calendar accounts to see if that was the cause.
It seemed to help the issue a bit because only 1 reboot so far today. But had another one while AFK at 6:24pm.
Here is the console output from the 6:24pm reboot:
Mar 30 18:18:28 Kurama identityservicesd[240]: <IMMacNotificationCenterManager: 0x7fdc43c569f0>: notification observer: com.apple.iChat notification: __CFNotification 0x7fdc43d6bdf0 {name = _NSDoNotDisturbEnabledNotification}
Mar 30 18:18:28 Kurama imagent[291]: <IMMacNotificationCenterManager: 0x7fc9b1e2d470>: notification observer: com.apple.FaceTime notification: __CFNotification 0x7fc9b1e90a90 {name = _NSDoNotDisturbEnabledNotification}
Mar 30 18:18:28 Kurama identityservicesd[240]: <IMMacNotificationCenterManager: 0x7fdc43c569f0>: NC Disabled: NO
Mar 30 18:18:28 Kurama imagent[291]: <IMMacNotificationCenterManager: 0x7fc9b1e2d470>: NC Disabled: NO
Mar 30 18:18:28 Kurama sharingd[268]: 18:18:28.130 : Purged contact hashes
Mar 30 18:18:28 Kurama sharingd[268]: 18:18:28.130 : Discoverable mode changed to Off
Mar 30 18:18:28 Kurama sharingd[268]: 18:18:28.130 : BTLE scanning stopped
Mar 30 18:18:28 Kurama identityservicesd[240]: <IMMacNotificationCenterManager: 0x7fdc43c569f0>: DND Enabled: YES
Mar 30 18:18:28 Kurama imagent[291]: <IMMacNotificationCenterManager: 0x7fc9b1e2d470>: DND Enabled: YES
Mar 30 18:18:28 Kurama imagent[291]: <IMMacNotificationCenterManager: 0x7fc9b1e2d470>: Updating enabled: NO (Topics: (
Mar 30 18:18:28 Kurama identityservicesd[240]: <IMMacNotificationCenterManager: 0x7fdc43c569f0>: Updating enabled: NO (Topics: (
Mar 30 18:18:28 Kurama identityservicesd[240]: <IMMacNotificationCenterManager: 0x7fdc43e68240>: notification observer: com.apple.iChat notification: __CFNotification 0x7fdc43d66200 {name = _NSDoNotDisturbEnabledNotification}
Mar 30 18:18:28 Kurama identityservicesd[240]: <IMMacNotificationCenterManager: 0x7fdc43e68240>: NC Disabled: NO
Mar 30 18:18:28 Kurama identityservicesd[240]: <IMMacNotificationCenterManager: 0x7fdc43e68240>: DND Enabled: YES
Mar 30 18:18:28 Kurama identityservicesd[240]: <IMMacNotificationCenterManager: 0x7fdc43e68240>: Updating enabled: NO (Topics: (
Mar 30 18:18:28 Kurama WindowServer[162]: device_generate_desktop_screenshot: authw 0x7fea14820400(2000), shield 0x7fea14853a00(2001)
Mar 30 18:18:28 Kurama WindowServer[162]: device_generate_lock_screen_screenshot: authw 0x7fea14820400(2000)[0, 0, 0, 0] shield 0x7fea14853a00(2001), dev [2560,1440]
Mar 30 18:18:28 Kurama WindowServer[162]: no sleep images for WillPowerOffWithImages
Mar 30 18:22:07 Kurama syslogd[40]: ASL Sender Statistics
Mar 30 18:24:52 localhost bootlog[0]: BOOT_TIME 1459376692 0
I have not reached out to apple support as of yet.
Thoughts?