To convert MBOX files to DOC format manually, first open the MBOX file using an email client that supports MBOX files, such as Thunderbird or Apple Mail. If you don’t have such a client, you can download Thunderbird for free and import the MBOX file into it. Once the emails are accessible, open the specific email you want to convert and select all its content by highlighting the text and images. Copy this content and then open a word processing application like Microsoft Word or Google Docs. Paste the copied email content into a new document, and then save the file in DOC or DOCX format by choosing the appropriate option in the “Save As” menu.