Every project must have UnInstall Property and this property is added to the project using registry key.
To include UnInstall registry keys,following procedure is followed.
Open or create a new project and identify the Project exe file with #RUN tag .If it is identified after opening the project the 'Registry {ALT+F4]' button is enabled.Now click on it and open the Registry Builder.Normally the saved project will have the UnInstall keys without which the project will not compile and build exe file.On opening the project the uninstall will be identified by the check box as given below.

If this does't appear and the project has already been a compiled one,then open the registry builder and close it after saving and on exit of registry builder the checkbox will be identified that 'UnInstall Supported'.
To add UnInstall Keys to new project,open the registry builder after identifying the project exe file.In the Registry builder you will find 'Option Tool' button.Click on it to open the option window which is given below.

It can be seen that the selected file version and other items required for the uninstall registry key will be added to the project and by clicking the 'Create' button ,the UnInstall registry keys will be added to the project.