What is DBX File? How to Locate DBX file on Windows?

In this piece of content, we will explain to you about email client, Outlook Express file extension; DBX file Format. We will try to cover and learn:

  • About DBX file
  • Where the DBX file is stored?
  • Technical detail of DBX


A DBX file is an email extension created by desktop email client Outlook Express. It is a collection of folders that saves OE mailbox as .dbx for a user profile; For example, common mailboxes are Inbox.dbx, Drafts.dbx, Sent Items.dbx, Deleted Items.dbx etc. Folders.dbx stores the master index for all the mailboxes. If it goes missing, Outlook Express re-index the mailboxes and recreate it again.

Microsoft Outlook Express was included with the Internet Explorer . It was the commonplace in the earlier versions of Windows OS. The program was used to send, store and receive emails. It used to be configured with a number of different email accounts for work.

But now it is mostly user is migrating usage of Outlook Express DBX file to Windows Mail(Vista) or Windows Live Mail(Windows7). s

DBX File Location

Mostly DBX files are saved in "Documents and Settings" within user directory and might be copied to another folder in order to create a backup of e-mail messages.

The default location where the Outlook Express dbx files are saved:


At the initial stage, the file structure of the DBX file denotes a basic hexadecimal arrangement. The header portion is considered as a file signature, which is shown at the starting of hexadecimal value: CLSID, i.e., content class ID. It is an identifier that is helping in differentiating the type of DBX.

Note: Whenever an email gets deleted, the header block and the data block length is updated that reflects the deletion procedure.

Recommendation: To access Outlook Express email data into Microsoft Outlook application convert .dbx file to PST format and import files within Outlook.

Technical Details About DBX File

Let's keep our eyes on the specific functions which are saved along with the DBX file while saving all emails or updating system settings. These particular functions are mentioned below:

Mail folder.dbx

Each and every folder of Outlook Express is saved as .dbx extension.


It symbolizes the index of the complete Outlook Express files. This file is further used to record the formatting of the entire folder, which is a bit similar to MBR.


It is the default email folder created for every user using Outlook Express. Inbox.dbx file is automatically created again if it gets deleted by any users. Some other items related to DBX file is outbox.dbx, draft.dbx, deleted.dbx, and sent.dbx.


It saves the pop3uidl letter information. For example, all the parameters of the server letter will be received and one, which is not having a letter will be reserved.


This file is created for those email account which is configured with IMAP configuration.

Newsgroup name.dbx

It is quite similar to other folders and each newsgroup is saved as .dbx file.

DBX File Specification
Type of File Email folder
Application Primarily Associated Microsoft Outlook Express
Organization Microsoft
File Extension .dbx
File Signature CF AD 12 FE

Final words

Both the professional and a home user operates Microsoft Outlook express like a approachable email program. It stores all the mailboxes information in DBX format. In this content, one goes to understand what's DBX file extension along side its structure and technicalities.