Set the Plays ("Play Count" before iTunes v9.2) of the selected tracks to a user-entered number (they will all be set to the same number). If this number is 0 then the Last Played date of each track will be erased. (iTunes has the ability to "Reset" Plays to 0 from a track's Info window.)
iCloud Music Library users should beware of a potential bug.
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Set the Plays of selected tracks.
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Displays files in iTunes Media folder not in iTunes track library
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Finds and displays any empty folders in the iTunes Media folder
downloaded 26m 43s ago
Move selected playlists to a new or existing folder
downloaded 27m 32s ago
Perform tasks on a batch of playlists; rename, delete, duplicate, merge, more
downloaded 59m 55s ago
Batch-change the Album Rating for the albums of selected tracks