System.Configuration.ConfigurationErrorsException: 创建 userSettings/Microsoft.SqlServer.Configuration.LandingPage.Properties.Settings 的配置节处理程序时出错: 未能加载文件或程序集“System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089”或它的某一个依赖项。系统没找到指定的文件。 (C:\Users\hp\AppData\Local\Microsoft_Corporation\LandingPage.exe_StrongName_ryspccglaxmt4nhllj5z3thycltsvyyx\10.0.0.0\useronfig line 5) ---> System.IO.FileNotFoundException: 未能加载文件或程序集“System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089”或它的某一个依赖项。系统没找到指定的文件。
 文件名:“System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089”
    在 System.Configuration.TypeUtil.GetTypeWithReflectionPermission(IInternalConfigHost host, String typeString, Boolean throwOnError)
    在 System.Configuration.RuntimeConfigurationRecord.RuntimeConfigurationFactory.Init(RuntimeConfigurationRecord configRecord, FactoryRecord factoryRecord)
    在 System.Configuration.RuntimeConfigurationRecord.RuntimeConfigurationFactory.InitWithRestrictedPermissions(RuntimeConfigurationRecord configRecord, FactoryRecord factoryRecord)
    在 System.Configuration.RuntimeConfigurationRecord.RuntimeConfigurationFactory.tor(RuntimeConfigurationRecord configRecord, FactoryRecord factoryRecord)
    在 System.Configuration.RuntimeConfigurationRecord.CreateSectionFactory(FactoryRecord factoryRecord)
    在 System.Configuration.BaseConfigurationRecord.FindAndEnsureFactoryRecord(String configKey, Boolean& isRootDeclaredHere)
 

解决：

删除这个文件
 
C:\Users\username\Local Settings\Application Data\Microsoft_Corporation\LandingPage.exe_StrongName_ryspccglaxmt4nhllj5z3thycltsvyyx\10.0.0.0\user.config 

安装SQL2008 提示 创建usersettings/microsoft.sqlserver.configuration.landingpage.properties.se