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After installing the pre-requisites a restart of the server may be required.
If you proceed without restarting then setup may be unable to proceed when it detects the pending restart.
After a check that all the pre-requisites are installed the setup wizard will move on to the next step automatically (if the check was successful). If this is the first server you're installing Microsoft recommends you install the Mailbox server role first (this can be either a Mailbox-only server or a combined Mailbox/Client Access server).
Depending on the server roles you are installing the pre-requisites vary.
There are also other cryptographic relevant RFCs for TLS.