A few things have changed in ver. 4.0.0 of CoolTrayIcon which means you may have to slightly adjust your previous projects that use CooltrayIcon or TextTrayIcon. 1) The IconVisible property is now default false in stead of true. The reason for this is that the tray icon would apparently show itself, regardless of the property being false, if CoolTrayIcon was used in a DLL file. This change means that you have to reset the property to true in your old projects, in case the value was originally true. 2) The StartMinimized property no longer exists. It has been replaced by the OnStartup event. This event has a ShowMainForm parameter, which you set to false if you don't want the main form to show when your app. starts. The reason for this change is that StartMinimized only worked at design-time, meaning you could not determine at run-time if you wanted to show the form or not. With the change it is now possible to have a user option for this in your app. See the StartHidden demo for an example.