In the Projects Window, right click on thelogical folder where you want to add a new logical subfolder containing the new files. Select Add Existing Items from Folders… from the popup menu.
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Open Dialog to Select Folder
Click on the Add Folder… button.
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Select Folder
Select a folder that contains files you want to add to the project. The folder need not reside in the project's directory. You can navigate to other directories if necessary.
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Add Folder(s) To Project
After selecting all the folders you want to add to the project, click the Add button.
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You should now see the folder(s) you selected as logical subfolders in the Projects Window.
Inside the folder are all the files it contains.
If the original folder on the hard drive contained subfolders, those will be added as logical subfolders as well. If they don't contain any files you need for the project, it is safe to remove them from the project.
If you need to work with Microchip Support staff directly, you can submit a technical support case. Keep in mind that many questions can be answered through our self-help resources, so this may not be your speediest option.