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what does this mean, the email address is correctAn error occurred while sending mail. The mail server responded: 5.1.0 From address is invalid (VM403). Please

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I am unable to send emails, and the following message occurs each time An error occurred while sending mail. The mail server responded: 5.1.0 From address is invalid (VM403). Please verify that your email address is correct in your account settings and try again. I know the email addresses are correct I have been using them continuosly

I am unable to send emails, and the following message occurs each time An error occurred while sending mail. The mail server responded: 5.1.0 From address is invalid (VM403). Please verify that your email address is correct in your account settings and try again. I know the email addresses are correct I have been using them continuosly

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