Yahoo allows you to send emails with attachments, and there are so many reasons why the attachments stop opening and viewing the contents. This might be because of PDF corruption. If someone has sent an email with a pdf attachment, there is a possibility that it will not open. If you wish to solve this, then you can restart the computer. It is possible that the other programmes might be interrupted, which interferes with the access of the PDF reader program and results in Yahoo PDF Attachment Problems. In such situations, a simple reset can fix the issue. You can also sign out of your account and then switch off the computer. Make sure that you wait for a few minutes also. And then switch on your computer again. This will help you solve the issue of the pdf attachment.