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Does the "Reliability Update 2 for the .NET Framework 4" (from KB2600217) include the changes from Reliability Update 1 for the .NET Framework 4 (KB2533523)? I.e. do I need to install both, or just the latest one?

For example, on a Windows Server 2008 R2 host on which just the RTM of Microsoft .NET Framework 4 has been installed, the file version of CLR.DLL is v4.0.30319.1. To update that server do I need to install first KB2533523 and then KB2600217? Or is is sufficient to just install KB2600217?

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up vote 1 down vote accepted

Per the MS Knowledgebase articles for the updates, you need to install both. Each update is a rollup of various hotfixes. The KB articles indicated that each update addresses a different list of issues, so the two updates are additive.

You can see this under the 'Update Replacement Information' heading in each article.

Reliability Update 1 for the .NET Framework 4

Reliability Update 2 for the .NET Framework 4

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I extracted both updates. They were self extracting CAB files containing an MSP file containing two CAB files, which contained all the files to be updated. The "Reliability Update 1" contained a few files that were not also contained in "Reliability Update 2". Therefore, these two updates target a different set of files for patching and must both be installed. – Andre Lombard Feb 21 '12 at 18:14

And I would like to add, that for me, the .net framework 4.5 update superceeded update2; it wouldn't let me apply it after installing 4.5 (and the symptoms I was checking for - postbacks not working in IE10 are gone)

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