我试图弄清楚可能出了什么问题。基本上，我无法编辑任何用户帐户。在用户管理器中单击编辑后，我会收到附加的异常。
任何建议将不胜感激。
Sitecore 版本为 6.6.0（修订版 130214）
这是日志文件中的异常：
**6136 11:49:33 FATAL An uncaught exception occurred
Exception: System.Web.HttpUnhandledException
Message: Exception of type 'System.Web.HttpUnhandledException' was thrown.
Source: System.Web
at System.Web.UI.Page.HandleError(Exception e)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
at System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
at System.Web.UI.Page.ProcessRequest()
at System.Web.UI.Page.ProcessRequest(HttpContext context)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
Nested Exception
Exception: System.NullReferenceException
Message: Object reference not set to an instance of an object.
Source: Sitecore.Client
at Sitecore.Shell.Applications.Security.EditUser.EditUserPage.PlaceInFrame(String urlString)
at Sitecore.Shell.Applications.Security.EditUser.EditUserPage.OnLoad(EventArgs e)
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)**