Hello Helen Spivey,
This issue usually happens if the scanning software did not finish saving the file completely before you tried to grab it or if it was saved as a temporary file in a hidden directory that your email application cannot read properly. To check what went wrong, I recommend opening the folder where your scans are normally saved such as your Documents or Pictures folder and trying to open the file directly by double-clicking it to see if the content shows up on your screen.
If the file opens fine on your computer but still appears empty when attached, try saving it to a different, easily accessible location like your Desktop using a slightly different name before attaching it again. Should the file be completely blank or show a size of zero kilobytes even when opened locally, please try running the scan once more and ensuring the scanning software gives you a clear confirmation that the save process is fully finished. If these steps help you successfully view and send your document, please feel free to accept the answer.
Tracy Le.