I opened an incident with Microsoft and their prognosis is as follows:
The machine is stuck as the result of the digiclsb.sys device not responding in a timely fashion to the shutdown request from the power subsystem. The vendor of the driver/device will need to be engaged for further investigation. This appears to be a Digiboard (a mutli port serial adapter). I recommend checking for any available updates, as well. This appeared to be the latest driver available on their web site however.
dump log excerpt removed
The vendor of the driver/device will need to be engaged for further investigation
We have a similar problem with our Digi-Neo 8 Port card. When stopping the service of the application, the process timed out. After this it is not possible to reboot the server.
Our current Version is 188.8.131.52. Do you have experience with the new Driver Version if the problem is fixed.
I’m very interested to solve the problem, because our software vendor doesn’t have any solution.
The latest released driver is 184.108.40.206. It should be used unless instructed to use a particular beta driver.
I have not seen any shutdown issues except one which only occurred with adapters other than the Neo and ClassicBoard, only in an IBM X series 236, if the adapter was installed in a “hot plug” type PCI slot.
The problem did not occur with the Neo and ClassicBoard. The problem is currently fixed for these other adapters with Windows drivers version 220.127.116.11 and newer. This problem with the ClassicBoard and Neo should be reported to Technical Support if you have not already done so.
We got a new Beta-driver from support that fixed our Problem. I think the problem depends on our specific server type ( 2 CPU). This problem was fixed in the new driver.