not using Volume License.
The CBS Persist log has something interesting in it at line 20536 (found while searching for the WMC "session Id")
2015-07-12 12:49:24, Info CBS Exec: Client forces reboot on session: 30457051_2904789849
2015-07-12 12:49:24, Info CBS Exec: Not trying hotpatching because root package is not hotpatch-aware: Microsoft-Windows-ProfessionalWMCEdition~31bf3856ad364e35~amd64~~6.3.9600.16384
Then all the more reason to use an ISO which already has KB3000850 in it (which was my main point, as well as wondering what other differences there would be between the two ISO packages.)
In any case, after creating a Restore Point this happens (at 23695)
2015-07-12 12:49:35, Info CBS Exec: End: nested restore point - complete.
2015-07-12 12:49:37, Info CBS Exec: Processing complete. Session: 30457051_2904789849, Package: Microsoft-Windows-ProfessionalWMCEdition~31bf3856ad364e35~amd64~~6.3.9600.16384 [HRESULT = 0x00000000 - S_OK]
2015-07-12 12:49:37, Info CBS Session: 30457051_2904789849 finalized. Reboot required: yes [HRESULT = 0x00000000 - S_OK]
2015-07-12 12:49:40, Info CBS Session: 30457051_3827705371 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:48, Info CBS Session: 30457051_3909022164 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:49, Info CBS Session: 30457051_3919335977 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:49, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:49, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:49, Info CBS Session: 30457051_3919335978 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:49, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:49, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:49, Info CBS Session: 30457051_3919492246 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:49, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:49, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:49, Info CBS Session: 30457051_3919492247 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:49, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:49, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:49, Info CBS Session: 30457051_3919492248 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:49, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:49, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:49, Info CBS Session: 30457051_3921054736 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:50, Info CBS Session: 30457051_3922929741 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:50, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:50, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:50, Info CBS Session: 30457051_3922929742 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:50, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:50, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:50, Info CBS Session: 30457051_3922929743 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:50, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:50, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:50, Info CBS Session: 30457051_3922929744 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:50, Info CBS Session: 30457051_3923242242 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:50, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:50, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:50, Info CBS Session: 30457051_3923242243 initialized by client WindowsUpdateAgent.
2015-07-12 12:49:50, Info CBS Failed to internally open package. [HRESULT = 0x800f0805 - CBS_E_INVALID_PACKAGE]
2015-07-12 12:49:50, Info CBS Failed to OpenPackage using worker session [HRESULT = 0x800f0805]
2015-07-12 12:49:54, Info CBS Session: 30457051_3969750980 initialized by client WindowsUpdateAgent.
2015-07-12 12:50:13, Info CBS mapping index is not updated.
But not having access to source or support documentation I have no idea what it means. (I'm not even perfectly clear on which messages pair with which of the preceding or following messages when an error is reported.) So that's why I would be using
ProcMon to supplement and clarify messages such as these. ProcMon's timestamp has much finer resolution than the second that we get in this log and besides there would be other trace events which would give them clearer context.
It kept trying to continue. Why? To try to provide a complete inventory of problems before aborting or to only abort when something really unrecoverable was found? Who knows?
Then I think (hope) we can skip down to 497915
2015-07-12 13:05:41, Info CBS Perf: Entering stage: Resolving
Hmm... Looks like there is a break in continuity. This file ends at the time shown (a few thousand lines further on) but the CBS.log starts at 13:09. And your WindowsUpdate.log shows that all kinds of stuff was happening in that interval.
Since there are such huge numbers of events which ProcMon would have to trace it may not be practical to use that tool in the usual way. E.g. normally it traces everything and its trace "file" is in RAM. So, I imagine you would have
to be selective about what events you would keep and where.
Supposedly there are alternative traces that we could invoke using netsh trace but I haven't tried that to say how or how useful it might be.
HTH