Favicon not working in IE

When viewing my WebHelp locally, generated with RH10, my favicon displays in FireFox and Chrome, but not in IE.

I have tried:

1. Using the default line: <link rel="shortcut icon" href="whstart.ico">
2. Using a different name for the favicon (e.g., "favicon.ico", "myicon.ico").
3. Using caps for "SHORT ICON".
4. Clearing my cache and retesting.
5. Using these alternate lines that specify type and put the image in a different folder location:
   <link rel="shortcut icon" type="image/x-icon" href="image/myicon.ico" />
   <link rel="icon" type="image/x-icon" href="image/myicon.ico" />
6. Using the old RH script to provide the http reference to the file location:
   <script language="javascript">
   <!--
   var sIcon="myicon.ico";
   var sPath=document.location.href;
   if (sPath.indexOf("http")!= -1)
   document.write("<link REL=\"SHORTCUT ICON\" href=\""+ sIcon +"\">");
   //-->
   </script>
7. Verifying that my .ico file is indeed an .ico file, and using alternate .ico files.

In all cases, the favicon works correctly in FireFox and Chrome, but does not work in IE.  I am using IE 11.  I tried switching the IE Document Mode to an earlier version.  No change.

Since the .png file format is supposed to work with IE, I tried using a .png file instead of an .ico file.  Still did not work in IE.

Any ideas?  Thanks!

Tim