STARTTLS
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TLS Client issues on Exchange server on premise
hi all, I have on-premise Exchange 2013. When I send email to 1 particular domain it returns "530 Must issue STARTTLS". This got me thinking that my TLS settings might be misconfigured. So i did try online CheckTLS tool. It appears that I have no problems sending encrypted emails (TLS1.2). When I send emails from my domain to my gmail account I can see TLS1.2 in the header also. However when I tested receiving it says "TLS is not an option for this server". It seems like i've tried everything from here https://learn.microsoft.com/en-us/exchange/plan-and-deploy/post-installation-tasks/security-best-practices/exchange-tls-configuration?view=exchserver-2019 The one thing I did not try is to disable TLS1.0 and 1.1, but can this be the problem? I also checked IgnoreSTARTTLS parameters on receive and send connectors, it is set to False. Can anyone help?Solved1.6KViews0likes3Comments