I already downloaded the stand-alone update previously and tried to install - same failure, same error.
However, as per another poster’s suggestion, I checked the BITS service and it had not been started. I started it and am attempting to run update now.
If BITS was on your service list, you have a different, less serious, problem than I had.
Did turning Bits on work? If not, google your error code and run the microsoft fixits that come up.