You're right. Fozzer (
https://www.mobileread.com/forums/showthread.php?t=32143) is having exactly the same problem. I sent a query to Sony by email and I'll post the reply. (that is assuming I get one)
If there is a permanent problem with the software, is there any problem with using Windows Explorer in loading & unloading books to & from the 505?
thanks,
Sundowner