Originally Posted by GingerTez
...but to get the library books to work on our PRS-505 readers we had to install the latest Adobe Digital Editions and the latest Sony Reader software and then we had to use DE to tranfer the books to the reader otherwise they wouldn't work.
I am assuming the other DRMd books you ran thru Calibre weren't ADE, or once again my limited knowledge is even more limited than usual. My understanding is that to use ADE with Sony you have to have Sony Reader software installed as well.
To use ADE, with bought or borrowed, means having to drag and drop them thru ADE, no matter what reader you use, so Sony only has that little extra requirement.