How to set the Taskbar Grouping Icon

Question

When my application opens too many windows the taskbar groups them into one button. Each window has its own icon, but the grouping icon is the default "unknown"-kind icon.

How can I set the grouping icon?

Answer 1

This comment from Raymond Chen indicates that the icon is coming from the exe itself, I would suggest using something like eXeScope to make sure that your application icon is being embedded properly, and maybe compare it with other exes that display proper behavior to do delta debugging.

Answer 2

The taskbar group icon can be set in the registry on a per application basis.

For explorer, this would be here:

[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Applications\explorer.exe]
"TaskbarGroupIcon"="C:\Windows\Explorer.exe,13"

Answer 3

Application taskbar group icon can be set in two ways

1. Through Project Properties:

   Click Project in solution explorer → right click → select properties → select Application tab → go to resoruces and change the default icon and select the newicon and save and build.

2. Through Registry(Dynamic):

   You have to create TaskbarGroupIcon key and value is "icon file with path" under "HKEY_CURRENT_USER\SOFTWARE\Classes\Applications\<>" If above keys are not present you have to create

   RegistryKey RegKey = Registry.CurrentUser.OpenSubKey(
      "Software\\Classes\\Applications\temp.exe",true); 
   RegKey.SetValue("TaskbarGroupIcon", "c:\temp.ico", RegistryValueKind.String);