fanfic_ebooks | Question to Sony Users/Sony Library Users

Thanks to a recent mishap with my PRS-505, I was forced to send it in for repairs only to find out that they no longer have the parts for it and, to make a long story short, they ended up sending me a brand new PRS-300 Pocket Edition for free. Which is fabulous (since it has twice the space) but now whenever I plug it in to sync, I get this warning message from the Sony Library: 'Unable to access due to insufficient permission'.

Which is odd because the first time I plugged it in, I had no problems with it, and I also had this problem with my PRS-505 and started using Calibre almost exclusively because of it. I've already checked out the Mobile Read forums but, unfortunately, the only answer I found didn't make much sense to me (I'm not tech savvy).

Which leads me to my question: do any of you other Sony/Sony Library users have this problem?

Honestly I don't mind using Calibre since it seems to be the superior e-book library but it annoys me to no end that I can't seem to use the software that comes with the device.