Since Yahoo Mail doesn't have an export feature, it's important to understand what options are available.

Print a hard copy.
Forward a single email to another email address.
Download your email from Yahoo Mail into a third-party app.
Copy and paste each email that you want saved into a text editor.

To backup all Yahoo emails to the hard disk, use an expert Mac Yahoo Backup program. This program is the most dependable way to back up and saves a whole Yahoo mailbox into more than 15 different file formats and email clients. Throughout the procedure, it upholds the initial folder hierarchy and strict data security. The easy conversion of Yahoo emails is made possible by Yahoo Backup Software, which provides 100% correctness. The tool offers instant backup without any data loss and is accessible to both technical and non-technical users. Additionally, it gives users the opportunity to convert only specific emails by using the email filter feature.

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Yahoo Backup Tool is the top-notch utility to backup Yahoo emails into PST, EML, MSG, MBOX, HTML, and PDF formats. Additionally, it migrates Yahoo emails into Gmail, Thunderbird, Office 365, Hotmail, IMAP, AOL, Office 365, etc. It provides 100% accurate and secure results. Download the free demo version of the software.