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Error: "Authentication Unsuccessful" sending Test E-mail from Company Maintenance in Sage 100 ERP

Note: Relevant ChilkatLog error information below, particularly in bold:

Unable to login to SMTP connection.
AUTH LOGIN
500 5.5.2 unrecognized command

Failed to login using LOGIN method
--SMTP_Connect
Failed to connect to SMTP server.
Failed.
--VerifySmtpLogin
--ChilkatLog

OR

With Exchange server
Using Microsoft SSPI NTLM.
response: 535 5.7.3 Authentication unsuccessful
Logon denied. Check username, password, and domain
NTLM authentication failed
Failed to login using NTLM method
--SMTP_Connect
Failed to connect to SMTP server.
Failed.
--VerifySmtpLogin
--ChilkatLog



Disclaimer

Operating System Warning
This solution requires advanced knowledge of your computer's operating system. Contact your system administrator for assistance. Modifying your Windows Registry incorrectly can severely affect system operations. Sage is not responsible for operation issues caused by incorrectly modifying your Windows Registry. Always create a backup of your data before proceeding with advanced solutions.
Resolution


On the Exchange Server enable Basic authentication.

In Exchange Server:
1. Locate SMTP Receive Connector
2. Right-Click and select Properties
3. Select Authentication tab
4. Check the Basic Authentication Checkbox
Note: This allows LOGIN method to be used by Chilkat
5. For Sage 100 ERP version 2013+, if email test still gets error then un-check "Offer Basic_authentication only after starting TLS" checkbox.

Note:

Version 2013 of Sage 100 ERP uses a different version of Chilkat client from older versions.

Unfortunately I already tried that and had no success (the resulting error message is a lot like the one I posted except with "Failed to login using LOGIN method" instead of "Failed to login using NTLM method"). Thank you for the reply though.

Have you tried re-entering the user name and password yet?