C# form icon isn't shown in taskbar when running on an other machine

I've programed a little piece of software (Visual Studio 2010) with multiple forms compiled in one exe. All forms have different icons assigned. These icons are shown correctly on the left top of the window and the task bar when I compile and run it on my notebook.

When I move the whole executables to my second pc the functionality of the program is ok except of this: For all forms which can be opened from the main form I see the same icon in the task bar. the window icon on the left top is shown correctly.

both computers are using开发者_如何学编程 win7 x64. and on both i don#t use this task bar pinning for my app. Seems that on my pc, the project icon is used instead of the form icons. But why?

so to summarize: laptop -> compile -> different form task bar icons as expected

pc -> same binaries -> all forms have the same icons in the task bar only! window icon is correct.

Hope someone can help!