Last summer, I happily updated my Adobe Acrobat from 5.0 to 6.0. The new acrobat displays file more clearly and smoothly. Both the text and image captures have become more powerful. And the software can READ the pdf file to you. It also has better security features. For example, my bank won't let me view my PDF banking statement unless I have updated my Acrobat 6.0 with some updates.
But when I was preparing for a grant proposal, I found I was trapped by this technology advancement. The Federal funding agency does not accept PDF file that is prepared by Acrobat 6.0. Huh?!
I first thought it won't be a problem since I probably could save my pdf file (again in Acrobat) as a file of a lower version, just as I can do in Microsoft Word, Excel, etc. But it didn't happen. Now I don't even remember what I did to circumvent this issue eventually. Maybe the struggle was too painful to remember. :)
Accidentally, when I was trying all the functions provided by Acrobat today, I found a command in the file menu called "reduce file size". It allows you to reduce the file to a new file that is of a smaller size and also compatible with a lower version of Acrobat. Bingo! It worked. Just in case I will forget this trick again, I am blogging it here.
Apparently, to the people at Adobe, the only reason one would want to lower the version of a PDF file is to reduce the size. :)