VS 2008 Server Explorer 添加数据库连接出错

Server Explorer 里面 Add Data Connection，选择后，点击 Ok 出现下列错误信息：

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Server Explorer
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Unable to add data connection.
Could not load file or assembly 'Microsoft.SqlServer.Management.Sdk.Sfc, Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91' or one of its dependencies. The system cannot find the file specified.
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OK  
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解决办法：
见这里的讨论：
http://www.microsoft.com/communities/newsgroups/en-us/default.aspx?dg=microsoft.public.vstudio.general&tid=89ee0e86-b8fc-40a7-a0e1-51ac4033302e&cat=en_US_38f7e3d1-40bd-4daf-941f-f45d2ff6ff9b&lang=en&cr=US&sloc=&p=1

需要到这里：
http://www.microsoft.com/downloads/details.aspx?FamilyId=C6C3E9EF-BA29-4A43-8D69-A2BED18FE73C&displaylang=en#filelist
下载 Microsoft SQL Server 2008 Management Objects 安装一下，重新打开 VS 就好了。

具体原因不明。