Previous Shutdown Cause: -2

Solution 1:

This is not normal digest-service[105]: digest-request: user=[redacted]

and this digest-request: guest failed with 22 proto=ntlmv2

Disable all and any Sharing! in Preferences- Sharing

The following does not harm:

• Restore system level permissions using Disk Utility

• Now restore the user level ACL's using the CMD-R (at boot) then select password reset option (but do not reset the password), instead choose ACL restore.

• Run this diagnostics in terminal

syslog -k Sender kernel -k Message CSeq 'n Cause: -' | tail | awk '/:/{$4=""; print}'

It will copy the result to the clipboard. Paste it here. If no result, the clipboard will be empty.

Log file 1

Log file 2

Solution 2:

Apple has decided that this is likely a hardware issue (tho they were not able to definitively identify it, they suspected the video card) and has agreed to exchange the unit for a new one.