C# 升级到.NET4后,在创建scriptManager时,我获得了YSOD

C# 升级到.NET4后,在创建scriptManager时,我获得了YSOD,c#,asp.net-4.0,C#,Asp.net 4.0,最近,我将一个现有的应用程序升级到.NET4。它编译并运行,但在登录屏幕之后,当我进入主页时,我会得到一个YSOD,说明: Could not load file or assembly 'Microsoft.Practices.EnterpriseLibrary.Configuration.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependenci

最近,我将一个现有的应用程序升级到.NET4。它编译并运行,但在登录屏幕之后,当我进入主页时,我会得到一个YSOD,说明:

Could not load file or assembly     'Microsoft.Practices.EnterpriseLibrary.Configuration.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified. 
突出显示的行是这样的

 <asp:ScriptManager ID="ScriptManager1" runat="server">
如果我重新加载页面,它会像一个符咒一样工作,直到AppPool重新启动——然后故事会重复


你们中有人知道为什么会发生这种情况吗?

你们在IIS中配置过使用ASP.NET v4吗?你安装了EntLib吗?您是否已将其安装到正确的x86/x64 GAC中?