This May 2018 Update for Windows 8.1, Windows RT 8.1 and Windows Server 2012 R2 includes cumulative reliability improvements in .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, and 4.7.1. We recommend that you apply this update as part of your regular maintenance routines. Before you install this update, see the "Prerequisites" and "Restart requirement" sections.
- All updates for Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2 require update KB 2919355 to be installed. We recommend that you install update KB 2919355 on your Windows RT 8.1-based, Windows 8.1-based, or Windows Server 2012 R2-based computer so that you receive updates in the future.
- If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you need before you install this update. For more information, see Add language packs to Windows.
Quality and reliability improvements
Note Step 4 can occur at any time relative to steps 2 and 3. However, step 4 must occur after step 1. Steps 2–4 must occur before the asynchronous call to UpdatePeer, posted by step 1. This will occur if steps 2–4 all occur in the same button-click handler.
1 Common Language Runtime (CLR)
2 Network Class Library (NCL)
3 Windows Presentation Foundation (WPF)
Additional information about this update
For more information about this update as it relates to Windows 8.1, Windows RT 8.1 and Windows Server 2012 R2, see the following article in the Microsoft Knowledge Base:
4103473 May 2018 Preview of the Quality Rollups for .NET Framework 3.5 SP1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7 and 4.7.1 for Windows 8.1, RT 8.1 and Server 2012 R2 (KB 4103473)
If your application serializes or deserializes data by using custom formatters that rely on a specific order of fields in the serialization stream, you might receive an exception error message when trying to deserialize an instance of the CustomAwareComparer object that was serialized on a previous versions of .NET Framework.
The exception error might resemble the following:
Exception type: System.ArgumentException
Message: Object of type 'System.Globalization.CompareOptions' cannot be converted to type 'System.Boolean'.
How to get this update
This update is available through Windows Update. When you turn on automatic updating, this update will be downloaded and installed automatically. For more information about how to get security updates automatically, see Windows Update: FAQ.
Microsoft Update Catalog
To get the stand-alone package for this update, go to the Microsoft Update Catalog website.
Windows Software Update Services (WSUS)
On your WSUS server, follow these steps:
- Click Start, click Administrative Tools, and then click Microsoft Windows Server Update Services 3.0.
- Expand ComputerName, and then click Action.
- Click Import Updates.
- WSUS opens a browser window in which you may be prompted to install an ActiveX control. You must install the ActiveX control to continue.
- After the ActiveX control is installed, you see the Microsoft Update Catalog screen. Type 4103473 in the Search box, and then click Search.
- Locate the .NET Framework packages that match the operating systems, languages, and processors in your environment. Click Add to add them to your basket.
- After you select all the packages that you require, click View Basket.
- To import the packages to your WSUS server, click Import.
- After the packages are imported, click Close to return to WSUS.
The updates are now available for installation through WSUS.
To apply this update, you must have .NET Framework 4.6, 4.6.1, 4.6.2, 4.7 or 4.7.1 installed.
You must restart the computer after you apply this update if any affected files are being used. We recommend that you exit all .NET Framework-based applications before you apply this update.