These are the conditions:
Using a shared Win 10 x 64 computer dedicated to Armory with the local area friend.
Originally configured successfully June, July 2017 with 0.96.0.4 and Core 0.14.2
(to be prepared for Seg-Wit, and the August 1 hard fork).
Over the past weekend an upgrade to 0.96.3992 with Core 0.15.1 had been successful after a number of attempts
(with TY to all in the forum for the excellent suggestions)
Further experiments to open Armory and close Armory seemed successful, Armory remained open overnight.
It had been thought that Window's updates had been disabled, but there was a forced reboot of the computer
for a Windows upgrade. Following the reboot, 0.96.3992 didn't open correctly and had to be forced into shutdown.
Following the prior recommendations for install the Armory folder was deleted.
0.15.1 database properly sync'd and then properly closed.
Subsequent attempts to load 0.96.3992 now hang at the opening rounded rectangle.
Observation of "process manager" insdicates that bitcoind.exe and ArmoryQT.exe are engaged.
ArmorydB.exe appears, but is not active
These folders are the successive Armory logs. The dBlog file has become circa 4.4 Gbyte and not practical to copy.
Four pastebin files in succession for the Armory Log
https://pastebin.com/rVK6bS8g https://pastebin.com/v6hCEWJz https://pastebin.com/TN8NGuZ0https://pastebin.com/03c4Afff Thank you for your advice and suggestions.
I have a guess it may be necesssary to fully reload 0.15.1 from scratch on the dedicated Armory computer.
This is the computer intended for install of the added databases
and to separate BCH from the legacy BTC positions.
There are two other computers used each of us - for our regular internet connections.
Each of those computers has 0.96.3992 and 0.15.1 fully operational and non contaminated
Each respective On Line computer has a dedicated off line computer for signing transactions.
Thank you again for your help.