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DBX File Extension

Outlook Express E-mail Folder
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What is DBX file?

DBX files store contents of a mailbox or mailboxes created by Microsoft Outlook Express, along with additional information for easier data access. DBX files have an upper size limit of 2GB, but the safest and most effective mailbox size is up to 300 MB – the size of given files depends on computer’s parameters such as amount of computer memory and CPU clock rate. Larger files can easily get corrupted, even during compacting process. DBX is a proprietary email format developed by Microsoft for Outlook Express, an email client application no longer included in Windows systems since Windows 7. DBX files were also be used for archiving email data and creating mailbox backup.

Outlook Express by default creates a DBX file for each user. Default program settings configure the folder location to be Documents and Settings, where users can find the following files:

  • Folders.dbx – this file store index of all mailboxes and is used to restore the file structure in case of file corruption or loss.
  • Offline.dbx – access data for IMAP or Hotmail,
  • Inbox.dbx – inbox messages,
  • Sent Items.dbx – sent messages,
  • Drafts.dbx – message drafts,
  • Deleted Items.dbx – ‘Bin’ for OE files.

Messages stored in DBX mailbox files can be imported to applications that replaced Outlook Express, namely Windows Mail and Windows Live Mail, using appropriate menu option. Many third-party tools for converting DBX into other formats, for example PST, are available on the market. DBX files should not be opened manually as it may cause Outlook Express not to function properly or effect in file corruption. Recovering the lost data requires use of special tools and it may not be possible to recover all the data.

Programs which support DBX file extension

Below is a table that list programs that support DBX files. Files with DBX extension, just like any other file formats, can be found on any operating system. The files in question may be transferred to other devices, be it mobile or stationary, yet not all systems may be capable of properly handling such files.

Updated: 09/18/2021

How to open file with DBX extension?

Problems with accessing DBX may be due to various reasons. Fortunately, most common problems with DBX files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The list below will guide you through the process of addressing the encountered problem.

Step 1. Install Microsoft Outlook Express software

Install software to open DBX file The most common reason for such problems is the lack of proper applications that supports DBX files installed on the system. The most obvious solution is to download and install Microsoft Outlook Express or one to the listed programs: Windows Live Mail, DBXtract, Aid4Mail. The full list of programs grouped by operating systems can be found above. If you want to download Microsoft Outlook Express installer in the most secured manner, we suggest you visit Microsoft Corporation website and download from their official repositories.

Step 2. Update Microsoft Outlook Express to the latest version

Update software that support file extension DBXIf the problems with opening DBX files still occur even after installing Microsoft Outlook Express, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of Microsoft Outlook Express is available. Sometimes software developers introduce new formats in place of that already supports along with newer versions of their applications. If you have an older version of Microsoft Outlook Express installed, it may not support DBX format. The most recent version of Microsoft Outlook Express is backward compatible and can handle file formats supported by older versions of the software.

Step 3. Associate Outlook Express E-mail Folder files with Microsoft Outlook Express

If the issue has not been solved in the previous step, you should associate DBX files with latest version of Microsoft Outlook Express you have installed on your device. The method is quite simple and varies little across operating systems.

Associate software with DBX file on Windows

Change the default application in Windows

  • Clicking the DBX with right mouse button will bring a menu from which you should select the Open with option
  • Select Choose another app → More apps
  • The last step is to select Look for another app on this PC option supply the directory path to the folder where Microsoft Outlook Express is installed. Now all that is left is to confirm your choice by selecting Always use this app to open DBX files and clicking OK.
Associate software with DBX file on Mac

Change the default application in Mac OS

  • Right-click the DBX file and select Information
  • Find the Open with option – click the title if its hidden
  • Select the appropriate software and save your settings by clicking Change all
  • Finally, a This change will be applied to all files with DBX extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Verify that the DBX is not faulty

Should the problem still occur after following steps 1-3, check if the DBX file is valid. It is probable that the file is corrupted and thus cannot be accessed.

Check DBX file for viruses
1. Check the DBX file for viruses or malware

Should it happed that the DBX is infected with a virus, this may be that cause that prevents you from accessing it. Scan the DBX file as well as your computer for malware or viruses. If the scanner detected that the DBX file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.

2. Check whether the file is corrupted or damaged

Did you receive the DBX file in question from a different person? Ask him/her to send it one more time. During the copy process of the file errors may occurred rendering the file incomplete or corrupted. This could be the source of encountered problems with the file. If the DBX file has been downloaded from the internet only partially, try to redownload it.

3. Ensure that you have appropriate access rights

Some files require elevated access rights to open them. Log out of your current account and log in to an account with sufficient access privileges. Then open the Outlook Express E-mail Folder file.

4. Verify that your device fulfills the requirements to be able to open Microsoft Outlook Express

If the system is under havy load, it may not be able to handle the program that you use to open files with DBX extension. In this case close the other applications.

5. Verify that your operating system and drivers are up to date

Latest versions of programs and drivers may help you solve problems with Outlook Express E-mail Folder files and ensure security of your device and operating system. Outdated drivers or software may have caused the inability to use a peripheral device needed to handle DBX files.

Do you want to help?

If you have additional information about the DBX file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on DBX file.

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