I have a computer still running XP that I use as a backup. Nook Study finally failed on that one. The last 5 books I bought from BN did not show up. Foolishly, I uninstalled it. When I reinstalled it, when I tried to log in, it said a network error. I managed to log out of Nook for PC and was able to log back in, but when I try to open the last book I bought, it asks for the name and credit card, which it never accepts.
Now I fear that it will fail on my Windows 7 machine also.
I hate B&N.