I have an application whose size is 16kb.
After adding an icon resource through the Project Properties menu, the application, as expected, increased to a size of 299kb.
Now, under Properties/Application when I set the Icon File to "Resource\IconName.ico" the file size again increases to 581kb.
Is this normal behavior? I understand that it increases when I add the icon as a resource, but not when I set the icon from the resources to the Application Icon.
Can anyone explain why this is happening?
EDIT:
Maybe a better question would be how can I set the Application Icon using an icon from the Properties/Resources section?
Yes, this is normal behaviour. Your icon isn't being stored as a resource twice (as suggested in some comments), it's simply being linked into the exe during compilation while also being stored as a resource. Since the icon is public-facing (i.e. explorer.exe accesses it directly when rendering the icon), you essentially end up with 2 copies of the icon in different formats:
If you really want to save this extra space, remove the embedded resource, change your application icon reference to point straight to the icon on disk, then, when you need a copy of the icon to assign to your forms, extract it directly from the assembly: