[anacreon]

I was extremely surprised recently when I couldn't read any PDF on the Sage - supposedly they weren't authorized by ADE - while there had been no change whatsoever to F/w and such. There was no problem with the kepubs (I don't read plain epubs).
I checked that the same PDFs had no problem on Elipsa, and decided to turn off the Sage.
I was happy that after turning it back on, all PDFs became readable again.
I wonder what type of problem would "de-authorize" reading PDFs but not kepubs, and would be solved by turning a device off then on.

EDIT: I strip DRMs on all books (PDFs or epubs or kindle files) as soon as bought, so ADE shouldn't have a say on them anyway. It is particularly necessary for PDFs since a higher proportion do not have TOCs than epubs'.