This can happen if there is a space after .pdf in your receipt name. Follow these steps to correct this:
  1. Go to Setup > Receipt Manager
  2. Find the published receipt template in use and click Edit
  3. Click 2. Upload File
    1. Look under Uploaded File Name
    2. The selected PDF contains a space after .pdf. To fix this, open the PDF on your computer, save it again, this time insuring that there is no space after the file extension
  4. Click Browse
  5. Select the new file without the space after the file name
  6. Click Upload PDF
  7. Click Next
  8. Click 5. Publish Template
  9. Click Finish