- Video or Audio content
- Executable files (or links to external executable files) or JavaScript
- Encryption of any type
- Embedded files, such as other PDF files
- Transparent objects (graphics) and layers
The reason for these limitations is to make sure that the PDF/A file contains everything required to display the file contents in the future, regardless of how the technology may change. For further information about the PDF/A check out the link below.
http://en.wikipedia.org/wiki/PDF/A
Word saves documents in the regular PDF format by default. To force Word to save in the PDF/A format, you need to follow these steps:
- Press F12 to display the Save As dialog box.
- Click the down arrow beside the Save As Type drop-down list and choose PDF as your file type.
- Click on the Options button. Word displays the Options dialog box.
- Make sure the PDF/A check box is selected.
- Click OK and close the Options dialog box.
- Enter a name for the PDF/A file in the File Name box.
- Click Save.