I have been using the Chilkat Email ActiveX for Delphi within our software for years with no issues. But, while setting up our software on a Windows Server 2008 machine, the email client keeps giving an error of "530 5.7.1 Authentication Required". The SMTP, port, SSL, and username/pw are correctly entered but always gives this error. I tried the same exact credentials on a Windows 7 and a Windows 10 computer and it sent the email fine with no errors. The error only occurs on a Windows Server 2008 machine. I was also able to test it on a second Windows Server 2008 machine and it gave the exact same error. I also tried another set of credentials on the Server 2008 machine and it gave the same error, but worked fine on Windows 7 and Windows 10. Any ideas why this error is only coming up on a Windows Server 2008 machine?