Hi Chris,

Maybe you should read:

https://docs.microsoft.com/en-us/office365/troubleshoot/o365-security/prepare-tls-1.2-in-office-365
https://www.microsoft.com/en-us/download/details.aspx?id=55266

Just part of the quote:

..."To provide the best-in-class encryption to our customers, Microsoft plans to deprecate Transport Layer Security (TLS) versions 1.0 and 1.1 in Office 365 and Office 365 GCC. We understand that the security of your data is important, and we're committed to transparency about changes that may affect your use of the TLS service.

The Microsoft TLS 1.0 implementation has no known security vulnerabilities. But because of the potential for future protocol downgrade attacks and other TLS vulnerabilities, we are discontinuing support for TLS 1.0 and 1.1 in Microsoft Office 365 and Office 365 GCC.

For information about how to remove TLS 1.0 and 1.1 dependencies, see the following white paper: Solving the TLS 1.0 problem.
More information

We have already begun deprecation of TLS 1.0 and 1.1 as of January 2020. Any clients, devices, or services that connect to Office 365 through TLS 1.0 or 1.1 in our DoD or GCC High instances are unsupported. For our commercial customers of Office 365, we will halt any deprecation enforcement of TLS 1.0 and 1.1 until the situation regarding COVID-19 stabilizes.

We recommend that all client-server and browser-server combinations use TLS 1.2 (or a later version) in order to maintain connection to Office 365 services. You might have to update certain client-server and browser-server combinations.

The following clients are known to be unable to use TLS 1.2. Update these clients to ensure uninterrupted access to the service......"

Best regards



I'm using Sergey Berezniker's CDO2000 code to send emails. Anyone know how to incorporate the use of TLS with this program? (Client is migrating from current mail server to Office 365.) Thanks in advance.