I've been reading and it seems that some email providers such as gmail/yahoo will black list certain IPs if they think that IP is spamming. On a shared account it is quite possible that someone can send out a number of emails such as a newsletter from a forum such as AA which would trigger that happening i.e. my emails may not go through to people if someone else on the shared server has caused black listing of the IP. I am curious about dedicated IPs on a vps. Right now I'm with Hostgator and according to this link even if using a dedicated IP available for an extra $2/month on a shared hosting account the emails still goes out through another IP other than the one assigned to the account. So in at least that situation the problem still exists. Does anyone know if that is what happens on a vps dedicated IP? Does every account on a VPS server use the same IP address for sending emails? I'm specifically thinking of ServInt VPS at the moment. I'm not ready to switch hosting providers at the time but am doing the research.