I have VestaCP installed on Ubuntu 14.04 x64 and have created multiple email adresses in VestaCP. I was trying to use roundcube mail client for the emails, but I face a problem when sending emails out.
Most of the servers would reject the emails and provide different error messages. Following is a mesagge from gmail:
I have not yet sent a single email succesfully, so previous spam is not a problem.
P.S. Receiving emails works as a charm.
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