In the Links tab of the Explorer dialog, right-click the link or folder containing links and choose Validate from the pop-up menu.

If the targets of the links do not exist in the locations to which the links point, the folder name and the links' names turn red. The link and folder names remain red until you revalidate and confirm that the target of the link exists in the specified location.

If the target file cannot be located the link will be broken. This happens if you delete or rename the target file. If you try to open the target of the broken link through Explorer, you will receive an error message.