You know the popup warnings that we've been ignoring -- Microsoft will deprecate Azure AD TLS 1.1, 1.0 and 3DES cipher suite:
It's time to pay attention. Microsoft means it it this time.
We run regular recursion tests to ensure our application on older hardware (when we migrate legacy systems such as our newly announced Kerio migration tools.) As part of that work, we have to register an Azure Active Directory application. Our scripts started failing a few weeks ago during our test on an older machine. The root cause -- Microsoft announced the deprecation of TLS 1.0/1.1 on January 31, 2022 (this machine was set to use TLS 1.1)
We're not going to reproduce the steps to enable TlS 1.2 that Microsoft published in November, 2021
- Install Update 3140245.
- Enable the registry values from the Enable TLS 1.2 on client or server operating systems section.
Microsoft provided a power shell script that does some of the work to check and enable TLS 1.2. It might be time to do this. The end of TLS 1.1 is near.