Viewing course notes on Sony Reader

Hey,

I’m having trouble reading the F4 notes on my reader, was really hoping I could view them on this so that I can study on the go.
I can read them on my PC & phone (screen too small to study!) but I get an error saying “protected page” or “invalid page” (have tried a few times!) on my reader. I presume this is something to do with the security settings as my reader is compatible with pdf.

Is there anything I can do to fix this? I’m studying Irish Law and there are no small pocket notes available so was relying on these to take everywhere with me!!

Thanks a million,
CB