when I use SMTP Authentication Support to send a test email.then error appear like:
SMTP Error: Could not connect to SMTP host.
Unable to send e-mail. Contact the site administrator if the problem persists.
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I have use hmailserver to build a local mail sever.
and I find php code with mime class from internet to creat php file.
and can use this php file send test email.

but failed to use drupal SMTP Authentication Support to send test email.
what is the problem?