Question
PHP contact form giving 550 5.1.1, “User unknown”
Hi, I run an Ubuntu server with Apache2. I have a PHP contact form in domain1.com. The contact form is configured to send messages using SendMail to info@domain2.com (domain2.com is a Zoho hosted email).
A few hours ago I was being able to send messages via contact form, but it suddenly stopped to work and started returning this error:
info@domain2.com… User unknown
Any idea?
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