Don’t worry in case you are not able to use Yahoo mail attachment feature. There might be the possibility that the file size is exceeding more than 25MB. It may contain some special characters or you can say the file may contain the virus. Numbers of possibilities are there in case you are confronting a trouble in using the attachment feature. If you are unable to figure it out, then consult the experienced Yahoo customer service care team
of engineers to sort out the trouble as soon as possible.