Sending failed; Reason 451
I have been getting this error message for the last 2-3 weeks, only when sending to certain people. Now I get it all the time and can't send anything. This in conjunction with my email not working at all as I was told I am using a different smtp server. I have been using this smtp server for months, now a rep tells me to use Zoho smtp server for email. Is this a requirement now? What changed that all of a sudden I can't send email to the same people and can't use my own smtp server.
PS - I attached a screen shot of error
Mark