title: Problem with window.open in FireFox
body: <p>I have problem with downloading files in Firefox. I tried to find solution in old posts but I didn't find anything.  I understand that solution is very simple, but I think today is not my lucky day :)</p>
  
  <p>Simple example. I try to call a web method from JavaScript and download a file.</p>
  
  <p>Client code:</p>
  
  <pre><code> &lt;script language="javascript" type="text/javascript"&gt;
           function Test() {             
               PageMethods.Test(onCompleted);
           }
  
           function onCompleted(result) {
               window.open(result);                          
           }         
      &lt;/script&gt;
  
  ........
  
   &lt;asp:ScriptManager ID="ScriptManager" runat="server" EnablePageMethods="true"&gt;
      &lt;/asp:ScriptManager&gt;  
  
      &lt;div&gt;
       &lt;input type=button value="Download" onclick="Test()"/&gt;
  
      &lt;/div&gt;
  </code></pre>
  
  <p>Server side:</p>
  
  <pre><code>[System.Web.Services.WebMethod]
  public static string Test()
  {
    return "\\Files\\test.zip";
  }
  </code></pre>
  
  <p>Folder 'Files' lies in root folder of Web application.</p>
  
  <p>For IE and Chrome, this code is working fine, and I can download the file.  But in Firefox, I get an error:</p>
  
  <blockquote>
    <p>Server Error in '/' Application.</p>
    
    <p>HTTP Error 400 - Bad Request. </p>
  </blockquote>
  
  <p>and in url I can see for example:
  <a href="http://localhost:1406/" rel="nofollow">http://localhost:1406/</a>\Files\test.zip</p>
  
  <p>How can I return the correct path to zip file?</p>