Installing Service Pack 1 for Office 2010 may cause the SharePoint Workspace (SPW) feature to be added to the installation, when it was previously set to "Not Available". This issue is the subject of Microsoft Knowledge Base article 2612800.

The screenshots below illustrate the SPW feature state as displayed in the Control Panel and the Office Customization Tool (OCT) when set to "Not Available":

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A related update was recently published to the Microsoft Download Center:

x86/32-bit (Office2010-kb2598245-fullfile-x86-glb.exe)
http://www.microsoft.com/download/en/details.aspx?id=29250

x64/64-bit (Office2010-kb2598245-fullfile-x64-glb.exe)
http://www.microsoft.com/download/en/details.aspx?id=29249

This update must be applied prior to the installation of SP1 to prevent the SPW feature from being added by SP1 or a later update.

Enterprise customers who are using the Updates folder for new installations of Office 2010 and including SP1 MSP files can use these steps to prevent the installation of SharePoint Workspace 2010:

1) Extract the contents of the update executable to a temporary location using the “/extract:<path>” switch (see KB912203 for addt'l switches).

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2) Note the contents and subfolder in the location of the extracted update:

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3) Copy the pre_rmaddlocal-x-none.msp and osetup.dll files, SP1 MSP files, and any other update or OCT generated MSP files into the Updates folder. The osetup.dll file can be found in the Admin subfolder, and the presence of this file will cause the pre_*.msp file to be applied before SP1, and after any OCT files.

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There are currently no plans to add this update to the Microsoft Update Catalog, as doing so would cause it to be offered to all Microsoft Update users. In this case, only users who have set the SharePoint Workspace feature to Not Available will be affected by the issue.

See the following articles for additional information:

KB2612800 Office 2010 SP1 installs SharePoint Workspace
http://support.microsoft.com/kb/2612800

KB2598245 Description of the Office 2010 update: March 29, 2012
http://support.microsoft.com/kb/2598245

Office Sustained Engineering and Release Team Blog post, "Update to Office 2010 SP1 to prevent unintentional installation of SharePoint Workspace"
http://blogs.technet.com/b/office_sustained_engineering/archive/2012/03/30/update-to-office-2010-sp1-to-prevent-unintentional-installation-of-sharepoint-workspace.aspx