This release is no longer recommended / available.

A bug was found in the May 2017 Preview of Quality Rollup installer that is incompatible with the .NET Framework 4.7 installer. The bug only surfaces when the May 2017 Preview of Quality Rollup (this update) and the .NET Framework 4.7 are installed, in that order.

• If you have installed the May 2017 Preview of Quality Rollup but not the .NET Framework 4.7, you are recommended to uninstall the May 2017 Preview of Quality Rollup.
• If you have installed the May 2017 Preview of Quality Rollup and the .NET Framework 4.7, you are recommended to uninstall the .NET Framework 4.7 and re-install the .NET Framework 4.7. This action will fix the underlying installer issue. You do not need to uninstall the May 2017 Preview of Quality Rollup in this case. In some cases, the May 2017 Preview of Quality Rollup update will no longer be visible in “Add or Remove Programs” after installing the .NET Framework 4.7.
• If you did not install the the May 2017 Preview of Quality Rollup, then you do not need to do anything.

See KB 4033488 for more information on the case where the .NET Framework 4.7 is installed after the May 2017 Preview of Quality Rollup.

The .NET Framework quality improvements that were included in the May 2017 Preview of Quality Rollup will be released as planned in a future non-preview release (intended for July 2017).

The remainder of the the text in this post is left for historical reasons. Please do not attempt to install the update.

We released the May Preview of Quality Rollup for the .NET Framework.

Preview of Quality Rollup releases are recommended for businesses that want to use and/or preview quality improvements as soon as they become available. These same quality improvements will typically be included in the following Security and Quality Rollup. You can read the .NET Framework Monthly Rollups Explained to learn more about how the .NET Framework is updated.

Quality and Reliability

This release contains 40 fixes from across the following product areas (number of fixes per area included below):

• ASP.NET (8)
• BCL (2)
• CLR (8)
• Entity Framework (1)
• Networking (1)
• SQL Client (4)
• Windows Forms (1)
• WPF (15)

Updates were made in the following .NET Framework releases. Release notes have been updated (for versions that have release notes).

• .NET Framework 4.6.2 (diff)
• .NET Framework 4.6.1 (diff)
• .NET Framework 4.6 (diff)
• .NET Framework 4.5.2
• .NET Framework 3.5

Note: This release does not apply to .NET Framework 4.7 and Windows 10. Please install the May 2017 Quality Rollup to get the same fixes if you are using .NET Framework 4.7 and/or Windows 10.

Security

This release does not contain any new security changes.

It contains previously released security changes, including the fixes in the NET Framework May 2017 Monthly Rollup.

Getting the Update

The Preview of Quality Rollup is available via Windows Update, Windows Server Update Services and Microsoft Update Catalog.

Docker Images

The Windows ServerCore and .NET Framework images have not been updated for this release.

Downloading KBs from Microsoft Update Catalog

You can download patches from the table below. See .NET Framework Monthly Rollups Explained for an explanation on how to use this table to download patches from Microsoft Update Catalog.

Previous Monthly Rollups

The last few .NET Framework Monthly updates are listed below for your convenience:

• May 2017
• April 2017
• December 2016

Note: Previously released security and quality updates are included in today’s release.