Encrypted remote access from home to windows server 12R2

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I would like to use Teamviewer as a medium to allow up to 20 users to access a shared folder on a Windows server 12R2 domain. The connection should be encrypted and password protected. The user devices include Windows 7/8/10, MS surface 3, Android and IOS.

Please advise what teamviewer software would achieve this and how it would be set up on theserver and user devices. 

Once I find out what I need, I will apply for a cost quote.

Any help is much appreciated.