Barbara,
Yes, I accessed the "updates" menu from the Help pull-down menu. I also accessed the updates using the Mac Terminal application with results shown in my original post. Regardless of whether I used the Help menu or the Mac Terminal app, the AAM tool still responded with:
Update Failed
Updates could not be applied
The error log file may help you in identifying the problem. The, try updating again. If the problems persist, contact customer support for further assistance.
The error log file read as follows:
Photoshop Camera Raw 8.5
There was an error installing this update. Please quit and try again later. Error Code: U44M1I210
Looking at the the output of the Mac Terminal app, it shows:
... hdiutil: attach failed - no mountable file systems
Is this relevant?
Regarding your follow-up message pointing to:
Update 12.1 installation errors | Photoshop Elements, Premiere Elements,
the files referenced in this link are present, are correctly named, and they are in the correct locations, so it would appear that these issues are not related to the ACR 8.5 update problem
Thanks