The Bulk Import dialog appears when you add a number of objects at once to the project, for example by dropping files from Windows Explorer onto the Files and Folders page or by importing a registry file. It allows you to assign the newly added objects to one or more components, so they will be installed and removed together. (You can reassign the objects later if you like.)
See Components and Features for more information.
The dialog contains some introductory text plus the following options.
Select this option if you don't want to assign the newly added objects to any component at this time.
Select this option to assign the objects to an existing component, then select the desired component from the drop-down list.
Select this option to assign the objects to a newly created component. You can accept the proposed new component name, or you can enter a different one if you prefer.
Tip: This is the most suitable option if you are adding non-file objects such as registry keys and values, because it makes it easier to manipulate the newly added objects as a group. For example, if you delete their component, you can optionally delete all the objects as well.
Select this option to assign all imported files to their parent folder's component, creating a new one as required.
Tip: This is the most suitable option if you are adding files and folders to the project.
Select this option to assign each object to a separate, newly created component. The new components will be named after the objects they control.
Check this box to detect .Net assemblies during import and create a separate assembly components for them, regardless of the other settings in the dialog box. This option is strongly recommended.