Window 2008 does support TLS 1.2. There is a free program that will help with the installation.
https://www.nartac.com/Products/IISCrypto
Running the program and saving should ensure the proper TLS setting is running on your server. A reboot will be required after applying these settings to your server.
Also on older window 7 machines, there are reported errors when connecting to outlook.
I’ve found a Windows 7 and Outlook 2016 fix for TLS 1.2 that has worked on a bunch of machines. TLS12-Enable.reg, which can be found here. This is TechNet for Exchange Servers, but the reg fix works.
SSL Protocols for Dovecot can be set to: TLSv1.2 !TLSv1.1 !TLSv1 !SSLv3 !SSLv2
Anyone with issues can run the regedit and it usually fixes the issue with Outlook 2016. Due to other issues, I don’t like 2012,13.
For EXIM, the default works in v72.0.5
For Apache, the default SSL/TLS Protocols work fine. (TLSv1.2)