@email@example.com (#mxago7a) The legacy charset ISO 8859-15 is used in Western Europe. It appears that some Unicode character is tried to be interpreted in this other encoding, which then fails. Sounds like something with
LC_CTYPE or friends. Any chance you’ve set this to
en_US.UTF-8 or something similar in your interactive shell? Try
env|grep -i utf-8. Your cronjob probably hasn’t set that.