我有一个网站，每当我调试它的浏览器给我一个错误

我不知道是什么导致这个错误，如果你需要看到我的代码只是让我知道，它的MasterPage。Master，附加到我的default.aspx。

这是我在浏览器中得到的错误:

Server Error in '/WebSite1' Application.
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Content controls have to be top-level controls in a content page or a nested master page that references a master page. 
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 
Exception Details: System.Web.HttpException: Content controls have to be top-level controls in a content page or a nested master page that references a master page.
Source Error: 
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.  
Stack Trace: 

[HttpException (0x80004005): Content controls have to be top-level controls in a content page or a nested master page that references a master page.]
   System.Web.UI.MasterPage.CreateMaster(TemplateControl owner, HttpContext context, VirtualPath masterPageFile, IDictionary contentTemplateCollection) +8690104
   System.Web.UI.Page.get_Master() +51
   System.Web.UI.Page.ApplyMasterPage() +15
   System.Web.UI.Page.PerformPreInit() +45
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +282


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Version Information: Microsoft .NET Framework Version:2.0.50727.5466; ASP.NET Version:2.0.50727.5456