The
MailMessage.To
property is not a string value; it is actually a
collection of email addresses
To add to this collection; you generally would use the
Add()
method, just like you did for the first recipient.
msg.To.Add(new System.Net.Mail.MailAddress(Email1, Name1));
msg.To.Add(new System.Net.Mail.MailAddress(Email2, Name2));
Reference:
MS Docs: MailAddress Constructor (System.Net.Mail)[
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