Open Windows Explorer. Select "Organize" at the top left of the window. Then, select
"Folder and search options."
Select the "View" tab at the top. Find and select the "Show hidden files, folders,
or drives" option. Then select "OK" at the bottom. Now you will be able to navigate
to the hidden folder where we need to delete some data.
Navigate to the following location (substitute your CampusID with the example given)
and delete any subfolder that appears under the "Offline Address Books" folder.