Email, Messaging, & Video Calls Email How to Use Yahoo Mail as a Virus Scanner Scan files for viruses by attaching them to messages in Yahoo Mail by Heinz Tschabitscher Writer A former freelance contributor who has reviewed hundreds of email programs and services since 1997. our editorial process Heinz Tschabitscher Updated on November 22, 2019 Email Yahoo! Mail Gmail Tweet Share Email Yahoo Mail automatically checks files you send as attachments for known viruses. Therefore, it's possible to use Yahoo Mail as a virus scanner. Instructions in this article apply to the standard web version of Yahoo Mail. Steps are the same for all web browsers. How to Use Yahoo Mail as a Virus Scanner To scan a file for viruses with Yahoo Mail: Create a new message and select the paperclip located in the bottom toolbar. Select the file you wish to scan, then select Open. Yahoo Mail tells you if it detects a virus within the file. If it detects no threat, the file is attached to the message, and a preview image appears. To remove the file, hover over the attachment preview, select the ellipses (...), then select Remove. Alternatively, delete the email and its draft to remove the attachment. Due to Yahoo Mail attachment size limits, you cannot scan files larger than 25 MB.