How to access old back ups?

Using Time Capusle for back up. Installed new hard drive on MacBookPro. Now cannot access files from back ups from before the new hard drive was installed. Using browse other back ups, have been able to locate them. Within the user folders, folder icons appear with red dot with horizontal white line and cannot be opened (except for the Public and sites folders). I have not found anyway to enter a password for the folders. Is there some way to access these files?