While attaching PDFs to a tax return can help support information on a tax return, there is a limit to the size of these attachments.
The total size of your PDF attachments must not be greater than 10MB. This will cause an Access Violation error when you attempt to send the return. Please consider reducing the resolution to minimize the file size.
Solution Articles:
Attaching PDF Files in UltimateTax Desktop
PDF Attachments for Federal and State Returns