When a desktop icon's property sheet offer no option to change the icon display, there may be a way to alter this in the registry.

If there is a DefaultIcon sub-key in the HKEY_CLASSES_ROOT\CLSID key, you can alter the icon display. Here are just some of the possibilities:

HKEY_CLASSES_ROOT\CLSID\\{208D2C60....\DefaultIcon Network Neighborhood
HKEY_CLASSES_ROOT\CLSID\\{20D04FE0....\DefaultIcon My Computer
HKEY_CLASSES_ROOT\CLSID\\{645FF040....\DefaultIcon Recycle Bin 3 Value entries
HKEY_CLASSES_ROOT\CLSID\\{00020D75....\DefaultIcon Inbox
HKEY_CLASSES_ROOT\CLSID\\{85BBD920....\DefaultIcon Briefcase
HKEY_CLASSES_ROOT\CLSID\\{FBF23B42....\DefaultIcon Internet Explorer

Alter the icon path in the Value entry to reflect the full path to the .ico, .exe, or .dll file. If you are using a .exe or .dll which contains multiple icons, you must add a ,xx where xx is the icon number.