How to upgrade Yarn from version 0.47 or earlier to version 0.52

- Replace the *.EXE and *.HLP files in your YARN directory with the ones
  from the new distribution.

- Older versions of Yarn stored your incoming mail in the file
  <home>\YARN\INBOX.  If you want to keep the messages in this file,
  move it to the <home>\MAIL directory.  For example, if the user's
  home directory is C:\JIM, type at the DOS prompt

        COPY C:\JIM\YARN\INBOX C:\JIM\MAIL\INBOX
