SharePoint 2010: Prerequisite installer fails on Windows Server 2008 R2 SP1

When running the SharePoint 2010 prerequisite installer (PrerequisiteInstaller.exe) on a Windows 2008 R2 box with SP1 installed, the installer may fail with the following error:

“There was an error during installation. The tool was unable to install Hotfix for Microsoft Windows (KB976462)”

Additionally in the prerequisite installer log, you may see a sequence similar to the following: 

<Date and Time>    -  Beginning download of Hotfix for Microsoft Windows (KB976462)
<Date and Time>    -  http://go.microsoft.com/fwlink/?LinkID=166369
<Date and Time>    -  Download of "Hotfix for Microsoft Windows (KB976462)" completed successfully
<Date and Time>    -  Installing Hotfix for Microsoft Windows (KB976462)
<Date and Time>    -  "C:\Windows\system32\wusa.exe" "C:\Users\<LoggedonUser>\AppData\Local\Temp\KB98ACC.tmp.msu" /quiet /norestart
<Date and Time>    -  Install process returned (-2145124329)
<Date and Time>    -  [In HRESULT format] (-2145124329)
<Date and Time>    -  Last return code (-2145124329)
<Date and Time>    -  Error: The tool was unable to install Hotfix for Microsoft Windows (KB976462). If Hotfix for Microsoft Windows (KB976462) 
                                 is already installed you may need to uninstall it and run prerequisite installer again.
<Date and Time>    -  Last return code (-2145124329)
<Date and Time>    -  Cannot retry

SP1 for Windows 2008 R2 already includes the fixes available in KB976462. The installer does not detect that the required fix is already there and tries to install it again which fails.

Run the prerequisite installer a second time. The second time it should recognize that an equivalent fix has already been installed and not try to reinstall it.

To prevent this problem from occurring -- for example, if you’re doing scripted installs of SharePoint 2010 on Windows 2008 R2 SP1, you need to configure the .Net Framework server feature before running the prerequisite installer using one of the following methods:

Automated steps to enable .Net Framework 3.5.1 features:

1. Create a PowerShell script file that includes the following:
        Import-Module ServerManager
        Add-WindowsFeature NET-Framework
2. Name the file PrerequisiteInstallerFix.ps1
3. Run the following command from an elevated command line
      %SystemRoot%\system32\WindowsPowerShell\v1.0\powershell.exe –ExecutionPolicy RemoteSigned <Path>\PrerequisiteInstallerFix.ps1

Manual Steps to enable .Net Framework 3.5.1 features:

1. Open Server Manager by clicking on Start, right click on Computer and choose Manage.
2. Navigate to the Features section and click on Add Features
3. Select .NET Framework 3.5.1 Features and all its children’s nodes:
4. Click Next and then click Install.

    Note: Reboot might be required.

Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use (http://go.microsoft.com/fwlink/?LinkId=151500) for other considerations.