eblib: Problem removing PDF DRM

[dramroo]

Hi all
Is protection Differs??!!
I done removed protection easily form file like this
hxxp://www.isg-egypt.com/rl/uploads/Oxford_American_Mini-Handbook_of_Gastrointestina.pdf
but when I try to remove it from this pdf I failed
here is the link
hxxp://www.isg-egypt.com/rl/uploads/Handbook_of_Optometry_and_Eye_Disorders.pdf

here is image of the error


both are from eblib.com at the same time
I realized that all books from publisher jaypee have a problem in DRM removal ...I failed with every method
could you help in that ??

thank you