What was a real problem was when I signed back in without being able to change the name in Explorer was that it could not find my desktop!!
Had to ctrl-alt-delete to get out. Redid the proceedure to set the name back to James. Whew - real moment of panic.
I was able to do all steps except rename folder in Explorer. Could not do this because "The action can't be completed because the folder or file is open in another program". Only open app showing in Task Mgr is Windows Explorer although dozens of background processes. Trying to change "james"...