Maybe one of these pages will help?

• How to Send an Attachment with Yahoo Mail (About,com Email Help page)
• How to add an attachment to an email (Yahoo Help page)
• Tips & How-To's - Attach Files (Yahoo Help page)

If you need more help and if no one else here has a solution, you could try Yahoo help at http://help.yahoo.com/

Thank you for your quick reply! Unfortunately, those links don't have the answer i am looking for. i know how to do it, but in the newest firefox the attachment button is dead... you can not click it. It works in other firefox versions, and in chrome etc. but not the new firefox :-(

Sorry, I don't have any other suggestions, except that I did find a thread on the Apple Discussions forum about a similar problem with Safari and Yahoo mail attachments:

https://discussions.apple.com/thread/3225265?start=45&tstart=0

Bru-Hed
Re: Safari doesn't work with yahoo mail: always getting beach ball
Feb 7, 2012 10:15 AM (in response to Anamariela)

Well, my problem with Yahoo Classic is different--I cannot click on some of the buttons! Very weird. No beach ball, but when I attach files to send an email and click on "Attach Files", nothing. Same with a couple others.

Going to try to install the new Flash as Mark suggested. Anyone else have this issue?

I probably should change to Yahoo's newer mail app but I just prefer the Classic version.

You might want to read the other replies in that Apple discussion and try the suggestions ... or just contact Yahoo help, if no one else replies here.