Someone who is more familiar with Plesk, than I will have to jump in on the Plesk question, but you need to make your own DNS entries for everything.
Setting up e-mail requires a solid knowledge of IIS, DNS, and PORTS, with 25, 110, 143, 587, 993. 995, and 5222 all being opened -- as required by TLS 1.1, TLS 1.1, and TLS 1.2 (all versions of SSL: SSL 1.0, SSL 2.0, and SSL 3.0 are depreciated - no longer used)
Don't try to depend on a third party tool to set this up - do it yourself.
Once you setup the DNS, you can setup the HOSTNAME MAPPING in IIS and add the domain in SmarterMail.
Bruce Barnes
ChicagoNetTech Inc
brucecnt@comcast.net
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Phone: (224) 444-0169
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