Keeping Track of Viewed Files
With a forensic license, the program can optionally keep track of which files were already viewed and flag them visually with a green background color around the tag. This is especially useful when reviewing hundreds or thousands of documents or pictures over a longer period, to avoid accidentially viewing the same documents multiple times. A file can automatically be flagged as already viewed when viewing it in full window or Preview mode, when viewing pictures in the gallery, or when identifying a file as known good based on the hash database.
When identifying duplicate files based on hash values, and one of the files has been marked as already viewed, then the duplicates can optionally be marked as already viewed, too. Similarly (only if the corresponding checkbox is fully checked), if files have been marked already as having duplicates and their hash values are available, when they are viewed, duplicates within any open volume will be marked as already viewed at the same time, but this is potentially slow when used in conjunction with the gallery. When viewing a file with further hard links (which are also duplicates), those will be automatically marked as already viewed as well, except in HFS+.
To manually mark files as already viewed, you can press Alt in combination with the cursor keys. Alt+Left removes the mark. You can also right-click the tag area of a file in the directory browser to mark it as already viewed or to remove that mark.
A directory is considered viewed if all the files and subdirectories that it contains are flagged as such.