Microsoft .NET Framework 4 Platform Update 1

The Microsoft .NET Framework 4 Platform Update 1 released today, 4/18/2011.

The Microsoft .NET Framework 4 Platform Update 1 is a platform update that is a set of new features that provides additional functionality for top customer requests and important scenarios.

The features that are enabled in this update are:

Windows Workflow Foundation (WF)

The Microsoft .NET Platform Update 1 consists of three packages:

  • Microsoft .NET Framework 4 Platform Update 1 (KB2478063)
    • This package contains the runtime files for the platform update. This package must be deployed on systems where applications that target the platform update are deployed.
  • Multi-Targeting Pack for Microsoft .NET Framework 4 Platform Update 1 (KB2495638)
    • This package contains reference assemblies and intellisense files for the platform update. This package is installed as part of the next package.
  • Microsoft .NET Framework 4 Platform Update 1 – Design-time Package for Visual Studio 2010 SP1 (KB2495593)
    • This package installs the previous two packages and configures Visual Studio 2010 SP1 with new .NET Framework targeting profiles, intellisense, and adds the state machine activities to the toolbox.

To develop workflow applications in Visual Studio 2010 SP1 that target the new Platform Update 1 functionality, the Microsoft .NET Framework 4 Platform Update 1 – Design-time Package for Visual Studio 2010 SP1 (KB2495593) must be installed. Once it is installed, the .NET Framework 4 Platform Update 1 (KB2478063) profile can be chosen when creating a new .NET application.

There are two new profiles added to Visual Studio when the Design-time Package for Visual Studio 2010 SP1 (KB2495593) is installed.

  •  .NET Framework 4 Platform Update 1 (KB2478063)
  •  .NET Framework 4 Client Profile Platform Update 1 (KB2478063)

When a new project is created with the platform update profile selected, the .NET Framework 4 Client Profile Platform Update 1 (KB2478063) is used. The .NET Framework 4 Platform Update 1 (KB2478063) profile builds on the .NET Framework 4 profile, and the .NET Framework 4 Client Profile Platform Update 1 (KB2478063) profile builds on the .NET Framework 4 Client Profile. The .NET Framework 4 Client Profile is a subset of the .NET Framework 4 that is optimized for client applications. For more information, see .NET Framework Client Profile.

To choose either profile or change the profile after a project has been created, right-click the project in Solution Explorer, choose Properties, and select the desired profile from the Target framework drop-down.

When either of these profiles is selected, the features in the platform update are available and the State Machine activities are available in the Toolbox.

To configure .NET Framework 4 Platform Update 1 on computers with Visual Studio 2010 SP1 that are going to be used to develop applications that target the functionality in the platform update, install Microsoft .NET Framework 4 Platform Update 1 – Design-time Package for Visual Studio 2010 SP1 (KB2495593).

To configure a computer on which applications that target the .NET Framework 4 Platform Update 1 are to be deployed, deploy Microsoft .NET Framework 4 Platform Update 1 (KB2478063) and the appropriate version of the .NET Framework 4.

For information on how to use the new state machine functionality in .NET Framework 4 Platform Update 1, see:


Comments (32)

  1. Fredrik Mörk says:

    The links to the first couple of KB-articles (in the the bullet list) seems to lead to editing pages rather than the articles themselves.

  2. Thank you Fredrik, links are fixed.

  3. Jeff Yates says:

    First stab at a bootstrapper package – I'm sure this has problems (especially since I guessed the exit codes and such).…/

  4. Jeff Yates says:

    Note that if you set the .NET Framework launch condition of your setup/deployment project to be the Platform Update 1 version of .NET, the setup.exe insists that you don't have it (even if you do).

  5. Hi Jeff, I am leaving up these comments in case other folks chime in, but we have taken the discussion offline and I will post an update to the blog once we get this figured out.

  6. Notre says:

    Are there any plans to push out this, particularly the runtime update, via Microsoft Update?

  7. Joseph says:

    Any update on the ADO.NET Activity Packs?

  8. Hi Joseph, WF team currently is actively working on the activities. Once they are ready, we will ship it out to our customers with a proper release vehicle.  We will send out an update once we have a release planned locked,. Thanks!

  9. Erica Mohler says:

    Notre, there are currently no plans to push out the Platform Update 1 on Windows Update. We currently only push out major Service Packs, MSRC's and broadly applicable fixes though Windows Update.

  10. Alex D' says:

    Few questions:

    is it mainly for WF? Or it make sense also for WCF Ria development?

    If I do WF with this Platform Update, can i use this WF in Sharepoint?

  11. Dan Ames says:

    Is the base .NET framework 4.0 being pushed out on Windows Update? We're trying to decide whether to upgrade our app from 3.5 to 4.0 and this is one consideration (i.e. if you are pushing it out then more people would have it already so we should upgrade.) Thanks, – Dan

  12. Allen says:

    What the hell is the story with that version name ".NET Framework 4 Platform Update 1 (KB"£$%^£$). S.E.R.I.O.U.S.L.Y. Pls tell me that's a typo that someone at Microsoft is really embarrassed about! I mean are you kidding me! If that is intentional, then Microsoft is seriously lossing the versioning plot.

    What is wrong with simply ".NET Framework 4.1" ? Seriously, what is wrong with that?

  13. LOL – the name is pretty… um… interesting.  The actual version number is 4.0.1

  14. Allen follower says:

    Amen, Allen.

    What is up with this moronic versoning scheme? At least 4.1 or 4.0.1 means something…

  15. Shane Courtrille says:

    As Ron mentioned the name is.. uhm.. a bit odd.  Maybe you can explain to us why MS has decided to forgo normal naming?

  16. I can't explain it.  I wasn't there when they made this decision.  

  17. Chris says:

    Wow. I agree with the other commenters about the utter stupidity of the version name. I am hestitant to install it simply to avoid the ugliness of having "NET Framework 4 Platform Update 1 (KB2478063)" appear in my Target Framework dropdown box. Seriously, who came up with this nonsense ?!?

  18. James says:

    This is 3.0/3.5 all over again. Sigh.

    Versioning, how does it work!?!

    Thanks for creating a pile of work for us again, why the **#@*(!! can't you just use !*@*(@*! version numbers like every bloody one else in the universe but you.

  19. Jaans says:

    Haven't you learned anything from the 3.0/3.5/3.5SP1 debacle.

    Just grow up… and go learn something before you dump these poor standards on those that have *real* software to write and support!

    If you want to show us you respect your customers, fix this disparity, and fix it properly.

  20. Michiel says:

    Microsoft, seriously, we have been over this before! Remember the 3.5 update when the community gave you valuable feedback about versioning? Apparently nobody was listening. Now we have Platform Update 1. What's next, Platform Update 1 Service Pack A? .NET Framework 4.5 again?

    At least the EF team got the message… I hope Somasegar kicks your ass!

  21. Matt Phillips says:

    Why is this being announced and described on someones personal blog? A blog for Scot's sake! Why not somewjere proper?

    You'll only be announcing things on Twitter next.

    (And don't get me started on the cretinous name it has been given)

  22. Tim Haynes says:

    Seriously.  Fix the version name.  And ditch the person who suggested it.  Platform Update?  Really?

  23. Richard Dingwall says:

    Is it april fools? How many minor non-backwards-compatible versions are you planning to release between .NET 4.0 and 5.0?

  24. Ron Jacobs says:

    I know the name be a little strange but this release is backward compatible.

    There will be more platform updates (don't know how many) who knows maybe there is a better name out there.

  25. DashNY says:

    Hey there, can't seem to get the new State Machine related activities to show up in the Toolbox. Got VS2010, SP1 and VS10SP1-KB2495593.exe applied. Switched the version in project's settings. Once I manually added <StateMachine> and <State> into the xaml file, it shows in the designer and compiles. But the toolbox still doesn't have those.

    Any ideas?

  26. Ron Jacobs says:

    StateMachine should show up in the toolbox when you open the Workflow Designer with a project that is using Platform Update 1 as the target framework.  If this is not happening you may want to reapply the Platform Update 1 patch.

  27. Patrick Assuied says:


    I have installed the Plaform update 1 on my development machine and it worked perfectly. Then I installed the Runtime update to our QA server (Win 2008 R2) and deployed my WF Service project tagged with targetFramework="4.0.1".

    When I access the service, I get the error:

    " The 'targetFramework' attribute in the <compilation> element of the Web.config file is used only to target version 4.0 and later of the .NET Framework (for example, '<compilation targetFramework="4.0">').

    The 'targetFramework' attribute currently references a version that is later than the installed version of the .NET Framework. Specify a valid target version of the .NET Framework, or install the required version of the .NET Framework."

    There's not much resource about this online so not sure where to go from here. I have tried to re-install the update and even restart the server, to no avail. At this point, I cannot really start using the state machine feature, which is sad.



  28. Composite state says:

    The composite state was removed from new state machine?

  29. Patrick, this is addressed in .NET Framework 4 update:…/2468871. See issue 9 of the KB article.

  30. Pam R says:

    I downloaded the service pack update VS10SP1-KB2495593, so I could go through the StateMachine tutorial. Now when I try to open Visual Studio Pro 2010 I get  the generic "Microsoft Studio has encountered a problem…" I tried repairing, removing and uninstalling, and re installing. I am a 30 trial install. Any suggestions.

  31. Pam R says:

    Never mind 😀