Step 1: Import mailbox data into Apple mail

Run Apple mail in your system.
Go to File >> Import mailbox option.
Now select the source of the MBOX file and click continue.
On browse location, choose MBOX file then click continue.
After the import process complete, click done.

Step 2: Create mailbox using Eudora

Add the MBOX file extension to the file that is imported.
For example, ABCMBOX needs to be changed to abcMBOX.mbx

Move this to the Eudora directory. The default location of the file: C: Documents and Settings user >> Application Data\Qualcomm\Eudora
Then, Open Eudora and double-click on ABCMBOX.mbx and Close the application.

Step 3: Import mailbox using Outlook Express:

Launch Outlook Express.
Now, Go to File >>Import >>Messages.
Choose Eudora from the list of email applications and then choose Next.
Now, browse the location to select the .mbox file and click on OK. Finally, click on Next>>Next >>Finish
In Outlook Express, the imported data can be used in the Local Folders

Step4: Import Mailbox from Outlook express to MS Outlook

To run into PST file format please ensure that MS Outlook is properly installed

Open MS outlook to export files.
Now, Go to the File>>import and export option.
Select import from another file and folder after which select next.
Next, choose Import Internet Mail and Addresses and click on Next
Select Outlook Express 4.x, 5.x, 6.x, or window mail. Click next
Select the file to import and export from the browser option and click next
Select to finish after the process completed.
The user can find the imported mailbox in your Outlook client.