A DBX file contains an encrypted database used by Dropbox, an online file hosting service. It stores encrypted information about a user's Dropbox in .SQLITE record format. DBX files may include recently modified files, the local path to a Dropbox folder, and the email address of the user.

DBX files are used by Dropbox to store various types of data and are similar to .DB database files but are encrypted. The name of the file indicates what type of information is contained in the file, such as filecache.dbx, notifications.dbx, photo.dbx, or config.dbx. DBX files are stored in various folders in Dropbox installation directories. The config.dbx is stored in the following locations: Windows XP: C:\Documents and Settings\%USERNAME%\Application Data\Dropbox\ C:\Documents and Settings\%USERNAME%\Local Settings\Application Data\Dropbox\ Windows Vista, 7, 8, 8.1, and 10: C:\Users\%USERNAME%\AppData\Local\Dropbox\ C:\Users\%USERNAME%\AppData\Roaming\Dropbox\ macOS: /Users/$USER/.dropbox/ Linux: /home/$USER/.dropbox/

A DBX file is a folder created by Outlook Express, a Microsoft email program. It contains email messages for a specific mailbox. DBX files are typically saved within the Documents and Settings user directory and may be copied to another folder in order to back up email messages.

DBX folders have names corresponding to their email mailbox. For example, common names are Inbox.dbx, Sent Items.dbx, Drafts.dbx, and Deleted Items.dbx. Folders.dbx stores the master index for all the mailboxes. If it is missing, Outlook Express will re-index the mailboxes and recreate it. DBX mail folders can be imported into Windows Mail (included with Windows Vista) by selecting File → Import → Messages, then choosing Import mail from an OE6 store directory and selecting the DBX folder you would like to import. DBX folders can be imported into Windows Live Mail (included with Windows 7) by selecting File → Import → Messages → Microsoft Outlook Express 6 and locating the appropriate DBX folder. The Stellar DBX to PST Converter program can be used to convert Outlook Express DBX files to the Outlook .PST format. You can then save converted files to Office 365, HTML, RTF, and PDF formats. NOTE: DBX folders should only be opened in Outlook Express or imported using another program. If opened or edited manually, they can become corrupted and cause Outlook Express not to function properly.