The "Select Modified Files" option is used to create Incremental and Differential backup sets, in contrast to selecting all files for a full backup set. The "Select Modified Files" option can be set at several places in UltraBac. From within the "Create New Set", "Create Set" or "Set Editor" screens.
After loading the directories from a drive into the "Set Editor", files can be selected using the "Select"/"Incremental" option path:

Figure 49: Incremental Backup Options
The "Select Modified Files" option automatically selects any file with its archive bit set on. This option when used in conjunction with the "Clear Archive Bit" option results in an Incremental backup set. Using this option without the "Clear Archive Bit" option results in a Differential backup set. Note: The "Clear Archive Bit" option is typically selected for all Full backups, especially when the Full backup is performed in conjunction with Incremental or Differential backups.
The other options available here create pseudo incremental backups. An example when this might be used is when the archive bits must not be cleared.
See UBQ: UBQ000080 Incremental, Differential and Archive Selections
Note: Refer to specific Agent documentation for explanations how the Agent interprets Incremental and Differential backups.
Note: The Set Editor's options: "Include", "Exclude", and "Select"/"Incremental" options apply only to the current files and folders as displayed in the right pane.
Note: When selecting "Select"/"Incremental" options, the logic is appended not replaced. To view and/or edit the current selection logic select "Select"/"Edit Selection Logic." The selection logic for the current files and folders can easily be cleared by selecting "Exclude"/(leave the * in the "File Selection Mask")/"Use Mask."