Hi @EcoAxis
Q1: Those computers which use basic authentication has met above requirement. How to fix these computers so that can use modern authentication?
Basic authentication will be turned off in all tenants beginning October 1st. This means that those machines that do not use modern authentication will cease to work.
However, Microsoft has put out an article that you can use the self-service diagnostic to turn basic authentication back on per protocol until 2023. This will buy you some time to transition your devices/Outlook to a supported version.
Q2. If basic authentication is disabled by MS after Oct-2022, will these clients cannot access Outlook?
As stated in the previous question, you can re-enable basic authentication until 2023. This will buy you time to upgrade your devices/software to the required versions. After this, your older devices/software will no longer be able to access their e-mails through Outlook due to not supporting modern authentication.
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