Changing the GUID might break backward compatibility in your installers. Are you sure you want to change the GUID?
Indicates that the current GUID is about to be replaced by a new one and reminds you that this might cause problems with earlier versions of the installers built from this project.
GUIDs (Globally Unique IDentifiers) are used to identify the product and its components. To ensure that new versions of an installer will recognize previous versions, it is important that the GUIDs of the product and its component remain the same. If not, the product or its components will appear as different, which might cause (parts of) the product to be installed or removed incorrectly, or not removed at all. Furthermore, if you change the product's GUID, it will no longer recognize earlier versions of itself during installation and might inadvertently overwrite a previous version without uninstalling it first.
If you are intentionally changing the GUID of the product or one of its components, for example to create a derived but different product or component, then you can safely change the GUID. (In fact, in that case you should change it.) However, if the product or component needs to remain compatible with earlier versions, then you should keep the existing GUID.