asp.net ！您的一个小问题？分数您说了算，有好多！ (0分)

Server Error in '/report' Application.
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Object reference not set to an instance of an object.
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.NullReferenceException: Object reference not set to an instance of an object.
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:

[NullReferenceException: Object reference not set to an instance of an object.]
Pub.WriteSysLog(String uerrip, String user, String loginfo) +422
eReport.Query.nav_logout.btnOK_Click(Object sender, EventArgs e) +619
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +108
System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +57
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +18
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +33
System.Web.UI.Page.ProcessRequestMain() +1277


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Version Information: Microsoft .NET Framework Version:1.1.4322.573;
ASP.NET Version:1.1.4322.573

分数您开口，好多的！

这个问题就是说：
Object reference not set to an instance of an object.
引用了不存在的对象呀，你检查一下
要不把Code帖出来