So building an app for a client, Windows and Android (Quest 2) we need to change the ico files.
We made an ico file using Canva for the image, then png to ico in an online converter… not too bad.
But after building using Unreal Engine 4.26 to Windows, the Exe image ico was still that of Unreal.
This is because an Ico file can contain multiple resolultions of itself (abit trippy but it makes sense).
The application using the Icon will get the correct size. So Windows explorer will get a small resolution from the ico file, while the task bar will get a bigger one.
We used: https://www.icoconverter.com/ to make ours.
Hope this help.