(FAQ) Unable to send mail from a BlackBerry device using a self-signed certificate in MDaemon
Why aren't the emails my users are sending out from their BlackBerry smartphones getting through to MDaemon via BlackBerry Internet Service (BIS), when I'm using a self-signed SSL certificate?
The BlackBerry Internet Service (BIS) servers currently do not support making SMTP connections to mail servers using self-signed certificates, or certificates generated by the same application that later provides it as verification of their security.
If your MDaemon server is setup to allow incoming SSL/TLS connections, or has the dedicated SSL SMTP ports enabled, with a self-signed SSL certificate, this may cause the connection from the BIS server to either error out, or get 'stuck', trying to send MDaemon messages your BlackBerry users are sending out from their phones.
To resolve this, contact a third-party certificate authority like GoDaddy, VeriSign, Comodo, or another to purchase an SSL certificate and install it into the Windows certificate store, then select it in MDaemon.
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