R hangs when attempting open existing *.R file

Aloha.

Just installed 'Arbor day' and what was an occasional problem is now
preventing me from loading even a script I was routinely running the day
before.

Anyone have any idea what might be wrong now?? I just get a beachball
and Force Quit tells me R is not responding.

Thank you.
J.

John Helly, University of California, San Diego / San Diego Supercomputer Center / Scripps Institution of Oceanography / 760 840 8660 mobile / http://www.sdsc.edu/~hellyj
ORCID ID: orcid.org/0000-0002-3779-0603