Changes to supported .NET Frameworks for Exchange 2013/2016

Edit: If you have already installed .NET 4.6.1, check this blog post on how to remove it (You Had Me At EHLO…)

Microsoft Exchange heavily relies on Microsoft .NET Framework. Because of this, Microsoft provides a matrix for the supported Microsoft .NET Frameworks. Mostly unknown is the fact, that Exchange doesn’t support the every Microsoft .NET Framework, and this is causing trouble sometimes. Some admins simply install the latest .NET releases because “it doesn’t hurt”. Well… it hurts!

Changes for .NET Framework 4.6.1

Microsoft has changed the support policy for .NET Framework 4.6.1 with the release of Exchange 2013 CU13 and Exchange 2016 CU2. Up to this versions, only .NET Framework 4.5.2 is supported. Starting with Exchange 2013 CU13 and Exchange 2016 CU2, Microsoft supports .NET Framework 4.6.1 together with a hotfix rollup (KB3146715 for Server 2012 R2, KB3146714 for Server 2012 and KB3146716 for Server 2008 R2). If you wish to install .NET Framework 4.6.1, make sure to install Exchange 2013 CU13 or 2016 CU2 first.

.NET Framework/ Microsoft Exchange Exchange 2007 SP3 Exchange 2010 SP3 Exchange 2013 CU13 and later Exchange 2016 CU2 and later
.NET Framework 3.5.1 X X
.NET Framework 4.0
.NET Framework 4.5 X
.NET Framework 4.5.1 X
.NET Framework 4.5.2 X X
.NET Framework 4.6.1
.NET Framework 4.6.2

¹ .NET 3.5 or 3.5.1 must be installed

² Supported with hotfix rollup (KB3146715 for Server 2012 R2, KB3146714 for Server 2012 and KB3146716 for Server 2008 R2)

Other .NET Framework versions

Microsoft .NET Framework 4.6.2 isn’t supported for any version of Microsoft Exchange. Other example: If you’re running Exchange 2010 SP3, don’t install anything above .NET Framework 4.5, not even 4.5.1. Check the Exchange Server Supportability Matrix for the supported .NET Framework for the Exchange version you’re running.

Side notes

Microsoft PowerShell is part of the Windows Management Framework (WMF). Microsoft Exchange only supports the WMF built into the underlying Windows Server version.

This also applies to Microsoft Outlook. I wonder how many Exchange projects fail because the Microsoft Outlook version, that is used by the customer, isn’t supported.