Do you have some kind of intrusion detection with active blocking running on the network? Are connections to the SMTP server restricted (in the properties of the SMTP service)?

An SMTP service installs by default as part of Windows 2000 server products and as part of the Internet Mail Connector (IMC) for Microsoft Exchange Server 5.5. (The IMC, also known as the Microsoft ...

Microsoft Corp. Thursday night issued a fix to patch a new vulnerability that could give an attacker user-level privileges on Windows 2000 systems running its Simple Mail Transfer Protocol (SMTP) ...

We are using Starlink in a remote place, which does not provide a SMTP relay server like our old (slow) cable modem ISP. A family member uses an email service she does not want to move away from that ...