Failed to generate a user instance of SQL Server due to a failure in starting the process for the user instance

Google了半天也没找到有具体讲这个问题的文档，不过最后发现解决这个问题也很简单，只要删除掉%Documents and Settings%\USERNAME\Local Settings\Application Data\Microsoft\Microsoft SQL Server Data下面的SQLEXPRESS文件夹就可以了。