“Cannot send email” and “not valid email address” error on iOS

If you are experiencing problems sending email from an iOS device (iPhone, iPad, etc) with an error headed "Cannot Send Email" and error message of " is not a valid email address and has been rejected by the server. The message has been placed in your Outbox." then you may need to set up SMTP Authentication, to log into your email account before sending emails. Please see our support article...

Configure your iPhone/iPad “Mail” app to access your email account

Getting started If you need to set up your email account manually, make sure that you know the email settings for your account. You can contact us if you are unsure of your O'Brien Media email settings. Then follow these steps: Go to Settings > Passwords & Accounts. Tap Add Account, tap Other, then tap Add Mail Account. Enter your name, email address, password and a description for your...