hello everybody,
our customer has a web server hosted outside our organization and on-promise exchange 2010 server,
they have a "donation" website, any external user can receive a bank account number in his email by typing his email and then " submit.
but they receive this error message
" An error has occured while sending the email:
535 5.7.3 Authentication unsuccessful"
how to deal with this issue? please help
Mohammad Naji senior exchange administartor