Questions:
1) Are you running out of disk space when producing the output? The first error message suggests that you are.
A: No, there is 190GB disk space available.
2) Are you writing to a single PDF file or a PDF file for each map page?
A: a PDF file for each map page.
3) When you say it worked up to page 28, does that mean PDF files are being generated?
A: yes, PDF files are being generated beautifully.
4) Thanks Jeff. I tried arcpy script you suggested and run it outside of ArcGIS. It generated 83 pages of map out of 107; then pop-up a message "not enough memory". However, of these 83 pages of map, I found a new problem, see the attached images. The text (microsoft word documents) for legends and disclaimers (OLE frames) do not come up on the PDF maps.
Regards,
Jiaorong