I think that they are referring to using the system restore program.

start > all Programs > accessories > system tools > system restore.

open the application and choose to restore to a prior date. At the calendar only those dates that are bold can be restored to. Click the date and follow the prompt.

Warning ....this will reset your whole system and you will lose what you have done between that restore point and today.....but also be warned that
1) it does not always work and the restore point cannot be brought back
2) some permanent deletions will not be restored


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There are programs that can be used to retrieve deleted files....I use Get Data Back and it has restored many a lost file for some of my clients... It is not free. but I think it has a free trial.
The program cannot be installed and used on the same drive that has the deleted files. The drive with the deleted files must be slaved or set up externally inorder to use the program.