Internet Explorer desktop icon changed to dark blue "e"

The default Internet Explorer desktop icon is light-blue "e". Sometimes, the icon color changes to dark blue, making it ugly. This happens if the defaulticon registry value is missing. To reset the color to defaults (as in fig 2), try this:
Click Start, Run and type:
REGSVR32 /i SHDOCVW.DLL

More Information

This registry key holds the icon settings for the Internet Explorer Desktop icon:

HKEY_CLASSES_ROOT
\CLSID
\{871C5380-42A0-1069-A2EA-08002B30309D}
\DefaultIcon

In the right-pane, (default) must be set to shdoclc.dll,-190
If the value is missing or incorrect, the icon color may be displayed in dark blue. If that does not help, see if repairing the icons using Tweak UI (for Windows XP) helps. Tweak UI can be downloaded from here:

v2.00 for XP | v2.10 for XP SP1 and above