we have an in house exchange server connected on 188.8.131.52 we suddenly are not getting about 50% of our sent e-mails though to the end users. sometimes we get a delayed message or soetimes a bounceback with odd refused messages like this one:
smtp;554 EMail from mailserver at 184.108.40.206 is refused. See http://spamblock.outblaze.com/220.127.116.11
Its odd because we dont own or use the ip address 18.104.22.168
any idea what could be causeing this? we have checked our ip aagainst sites like spamhause and its clear.