Object reference not set to an instance of an object.

[NullReferenceException: Object reference not set to an instance of an object.]
   SchoolAdmin_schoolsetting.Page_Load(Object sender, EventArgs e) +71
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +15
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +34
   System.Web.UI.Control.OnLoad(EventArgs e) +99
   System.Web.UI.Control.LoadRecursive() +47
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1061

这个可能是怎么回事呀，在我的电脑上很好的运行，上传到服务器上就有了这种情况。

博客园也出现过这种情况怎么解决呀？http://space.cnblogs.com/group/topic/7599/