Hi!
What is the
source of your .pdf that doesn't work? Public Domain scanned book or commercially/professionally prepared .pdf?
I had an issue loading Google .pdf ebooks that employ JPEG2000 (scanned) images as those don't load properly on the iLiad. The work-around I found was to "optimize" the .pdf for 1.4 version or earlier using Abode Acrobat Pro or similar software. The re-saved version then worked well!
Other than that my iLiad reads .pdf ebooks quite well. Make sure you install one of the
updated .ipdf's (I use jharker's fullscreen version on my iLiad 2nd edition v2.12!)