When I have taught this class in the past I have found that some students had multiple sets of folders and files on their computers, and they would do the homework for one week in one set of files and homework for another week in another set of folders. To repair the damage, they would have to try to reconcile the work in two different sets of files. It is so difficult to reconcile them that it is almost easier to start over than to try to reconcile two or more sets of files. The most important thing to remember is WHERE you have your website folders and files, and to make sure that when you are coding that you are always in the right folder.