Show desktop icon
Drag the Show Desktop icon into a Notepad window. You now should see:
[Shell]
Command=2
IconFile=explorer.exe,3
[Taskbar]
Command=ToggleDesktop
Now replace the third line with something like
IconFile="C:\path\toyour\icon.ico"
click File > Save
That's it. Change will take effect after next reboot.
Internet Explorer icon on desktop
This can be changed in the registry at
HKEY_CLASSES_ROOT\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\DefaultIcon
Backup (export) the key, then replace "shdoclc.dll,-190" with the full path to your icon "C:\path\toyour\icon.ico". Make sure to include the quotes.
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