Hi, Phil.
By default (unless you choose otherwise), Quicken keeps its current up-to-the-minute data fileset (.qdf, plus .qph, .qtx, etc., depending on how YOU use Quicken) in the same folder with its executable files: C:\Program Files\ QuickenW.
It also keeps weekly backups of your whole data fileset in a subfolder that it always names BACKUP: C:\Program Files\QuickenW\BACKUP. By default, it will keep 5 sets, with the newest named QDATA1.* and the oldest QDATA5.*, incrementing the digit each week until it deletes the *5 set after the 6th week, and writing the newest set to QDATA1.*.
In addition, of course, you should make "manual" backups to one or more locations of your choice, including at least "milestone" backups to removable media that you can store separately from the computer in case of fire or other disaster. To make these backups, just click File | Backup, or press +B, or click the Backup button on the Tool Bar. If you forget, Quicken will remind you to do this after every 3 (by default) times that you exit Quicken.
Thus, you should always have at least 3 copies of your full fileset: the current set in QuickenW; the most recent weekly backup in QuickenW\BACKUP; and your latest manual backup wherever you put it.
If you use Quicken's tools to backup or copy your data, it will automatically include all the files in your fileset. If you use Windows Explorer or other non-Quicken tool, you must be sure to include ALL the data files, not just the .qdf file.
RC