I am using Exchange 2000 and was suddenly unable to send emails. (No problem receiving). I eventually found out that to reduce the problem of 'Spamming' to their customers, my ISP had blocked off port 25 and blythly announced that they no longer supported mail servers like Exchange on this service (cable) and - er - good luck! I won't bore you with the details, but it is not a simple matter to change either my service (can't go to DSL) or service provider. It occurs to me that :- 1. Others may have suffered the same fate as me. 2. There may be a work-around for this problem. Can anyone help me?