Icon Of Notepad++
On Windows, applications are represented by visuals of varied sizes, from 16x16 to 256x256 pixels, by the operating system, with a consistent look and feel.
These are provided by the application and looked up by Windows when it starts it, so changing an icon at runtime is not an option. Changing the icon of an executeble is possible using some extra free shell extensions or tools like ResHacker.
Before v5.8.4, Notepad++ had a single icon (family) . A new icon was introduced then, but a release of Notepad++ with the old icon is available on the official download page (http://notepad-plus-plus.org/release/6.6.6)