I've had several problems which I'm sure are related to my DNS configuration. Here's my record for my main domain: "A" RECORD: @ 188.8.131.52 www 184.108.40.206 netsrvr1 220.127.116.11 smtp 18.104.22.168 CNAMES (Aliases): None MX (Mail Exchangers) : 0 @ netsrvr1.bitterbrushnet.com TEXT: @ v=spf1 a ptr mx:smtp.bitterbrushnet.com -all My reverse DNS record is configured as: 22.214.171.124 >>> bitterbrushnet.com My ISP only allows one entry per IP address. Is this normal, or is it just them? I had problems (mail test failure) when I used smtp.bitterbrushnet.com in the MX record. When I changed it to netsrvr1 (my real hostname as configured during initial installation) I was able to receive mail. So, (1) what is the optimum zone file configuration, and (2) how does this apply to virtual hosts? Do their MX records read "smtp.virtualhost.com"?