Check out Advik Gmail Converter application for Windows. This tool is specially developed to extract attachments from Gmail account. You can also download Gmail emails to the computer in more than 15+ file formats.

Steps to export all attachments from Gmail are as follows;

1. Run Advik Gmail Converter in your system.
2. Enter your Gmail login credentials and sign in.
3. Select mailbox folders and click Next.
4. Choose "DOC" as a saving option from list.
5. Click convert and analyze the process.

The wizard will start exporting all attachments to a separate folder.
Note: Apply Advance Setting for selective attachment extraction from Email.
Download : https://www.gmailconverter.com/dl/gmail-converter.exe
Source : https://www.gmailconverter.com/

Download Rediffmail Backup Software to PC by Advik Software in order to export it's mailbox to local hard drive. This software is one of the finest innovation by Advik developers. You can export and save complete Rediffmail Backup to PC in multiple formats such as PST, EML, MBOX, MSG, DOC, PDF, HTML, TEXT, TGZ, RTF, XPS, Lotus Notes etc.
Also you can migrate your emails from Rediffmail to Gmail, Office 365, Thunderbird, G Suite, Yahoomail, Windows Live Mail, Another Rediffmail Account, Outlook.com etc email clients without any additional configuration.
Download link : http://www.adviksoft.com/dl/advik-rediffmail-backup.exe