Can someone please explain to me if there is some setting somewhere I need to check off or toggle on to allow yahoo mail to add attachments? I cannot for the life of me figure out why I can't add attachments in Yahoo mail. It's not the size of the attachment, they are all within the Yahoo limits. I can attach in Gmail no problem. I go to my PC and attach the file as well. I go to my iMac and that same file that worked on the PC just will not attach at all on the iMac. Any suggestions?