Sign up ×
Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

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?

share|improve this question

2 Answers 2

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

share|improve this answer
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)

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.