# Taskbar Button Overlay

## Content



The overlay image is used to communicate information with a user about the state of an application. The [C1TaskbarButton](/componentone/api/win/online-winpack/dotnet-framework-api/C1.Win.C1Win7Pack.4.8/C1.Win.C1Win7Pack.C1TaskbarButton.html)s overly icon can be set at design time in the **Properties** window or can be set via code for run time interaction. It is more common to see this property set when a specific event occurs at run time.

The [OverlayIcon](/componentone/api/win/online-winpack/dotnet-framework-api/C1.Win.C1Win7Pack.4.8/C1.Win.C1Win7Pack.C1TaskbarButton.OverlayIcon.html) property takes type [System.Drawing.Icon](http://msdn.microsoft.com/en-us/library/wkat843k) and requires the size of the icon to be no more than 16x16 pixels.

For task-based help about overlays, see [Adding an Overlay Image to the Taskbar Button](/componentone/docs/win/online-winpack/windows7controlpackf5/c1taskbarbuttontaskb/workingwiththetaskba/addinganoverlayimage).