The .NET Framework 4.7 has been available for about a month and is expected to be distributed soon via Windows Update. Even if .NET 4.7 is already supported on Windows Server, you should be careful with Exchange Servers. Here is the current support matrix for Windows Server and .NET 4.7:
The .NET Framework 4.7 is supported on the following Windows Server versions:
- Windows Server 2016
- Windows Server 2012 R2
- Windows Server 2012
- Windows Server 2008 R2 SP1
However, .NET Framework is not yet displayed in the Exchange Server compatibility matrix:
Source: Exchange Server Supportability Matrix
As it is in the Problems in the past with updates of .NET Framework in connection with Exchange Server, .NET 4.7 should not be installed on Exchange Servers to avoid compatibility problems. The corresponding note can also be found in the matrix:
Support for .NET 4.7 will certainly be delivered with the next CU, so it's worth being patient here. I am not aware of any problems so far, but that doesn't mean anything.
This describes how the installed .NET version can be determined:
https://msdn.microsoft.com/en-us/library/hh925568(v=vs.110).aspx
If .NET 4.7 is already installed, I would currently uninstall it until it is officially released.
Update 27.06.2017: So far there seem to be no problems with .NET 4.7, but it is not yet officially supported.