Problems setting icons in Windows 7

Question

I am trying to create an application icon. I took a bunch of * .ico files (one for each size) and merged them into one * .ico file. I see them all right. I have 16x16, 32x32, 48x48, 64x64 and 128x128 icons (all 32 bits with transparency).

However, when I create my application (a standard Windows Forms application written in C #) and look at the icon in Windows Explorer, it looks great in the first few sizes (up to 48x48, I think .. "Medium") but if I use modes displaying "Large" or "Extra large" in Windows Explorer, I just see the 48x48 icon (I think) in a larger box.

How can I make Windows Explorer recognize larger icons? What am I doing wrong? Has anyone seen this problem before and pointed me in the right direction? I assume that there is a problem with how the * .ico file or formats are created ... but I cannot find any hints anywhere.

Answer 1

As far as I understand, as soon as you reach a certain size (and it can be 48x48), Explorer will go look for the 256x256 icon and scale it to the desired size.

128x128 is not a standard icon size, and Explorer may not search for it. You can show icons up to 256x256 in Explorer (Extra Large Icons), although you can size between them. If the size of your icons is, say, 192x192, then it’s better to look bigger and scale it, instead of making a small image and scale it - so you better add a 256x256 image anyway, and not 128x128.