Yahoo Mail attatchment trouble

Hello,
So my aunt has an e-mail account with yahoo, and she regularly send QuickBooks attachments to her accountant and it was working fine; but now it just sits their downloading the attachment and never getting to the point where she can send it and it keeps making drafts like every minute or so while the attachment is trying to load. I tried to send it from my g-mail account, but unfortunately halfway through the attachment download the attachment failed. if anyone could help it would be greatly appreciated.