if you have a dedicated IP address for your site, you can request for it to be removed from various blacklists, however, if you are on a shared server, I wouldn't do that, because you can't control the other sites on that server that may be still sending out spam.
~Sovereign
Just a heads up I've been trying to find good and inexpensive hosting site and so far I've had no luck.
The worst by far is Netfirms since they were bought out and moved to Boston they are absolutely pathetic both from a reliability stand point and also from a core competencies of support staff stand point.
Hostpapa is the host I've been testing lately and they were fine for a year but I've been having problems lately. One of hostpapa's ip is being blocked by spamhaus and unfortunately my domain resides in this server as a result most of my email is bouncing back. This should not be a difficult problem to resolve but I'm finding Hostpapa's support also unresponsive, uncaring and plain awful. I guess you pay peanuts you get monkeys...

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