asp.net - Cannot use a leading ../ to exit above the top directory

Question

I have a asp.net web site with it we have admin area with login page for admin only and all site is allowed for all - i need to ask how to define the right security configuration for it as i get this error

Cannot use a leading .. to exit above the top directory. 
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: Cannot use a leading .. to exit above the top directory.

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): Cannot use a leading .. to exit above the top directory.]
   System.Web.Util.UrlPath.ReduceVirtualPath(String path) +8862087
   System.Web.Util.UrlPath.Reduce(String path) +52
   System.Web.Util.UrlPath.Combine(String appPath, String basepath, String relative) +214
   System.Web.UI.Control.ResolveClientUrl(String relativeUrl) +180
   System.Web.UI.WebControls.Image.AddAttributesToRender(HtmlTextWriter writer) +68
   System.Web.UI.WebControls.WebControl.RenderBeginTag(HtmlTextWriter writer) +20
   System.Web.UI.WebControls.WebControl.Render(HtmlTextWriter writer) +20
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer) +163
   System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer) +32
   System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output) +51
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer) +40
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.Control.Render(HtmlTextWriter writer) +10
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +134
   System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +19
   System.Web.UI.Page.Render(HtmlTextWriter writer) +29
   System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter) +27
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer, ControlAdapter adapter) +99
   System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +25
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1266

my configuration file :

 <authentication mode="Forms">
  <forms name=".ASPXFORMSAUTH" protection="All" loginUrl="Admin/LoginPage.aspx" path="/" enableCrossAppRedirects="true">
  </forms>
</authentication>
<authorization>
  <deny users="*" />
</authorization>

Answer 1

What this means is that your web page is referring to content which is in the folder one level up from your page, but your page is already in the website's root folder, so the relative path is invalid. Judging by your exception message it looks like an image control is causing the problem.

You must have something like:

<asp:Image ImageUrl="..foo.jpg" />

But since the page itself is in the root folder of the website, it cannot refer to content one level up, which is what the leading .. is doing.