Hi Imacri, your posts are always very informative. Thanks for pointing out the security patch that I now lack. I'll try to remember not to open iTunes Tutorials until a DEP-compatible update becomes available. I certainly would not recommend downgrading for everyone with this issue, nor did I mean to suggest that v. 11.0.5.5 was the right choice for everyone. I chose that version after looking at the "date modified" of the recent backups in my Previous iTunes Libraries folder. (I'm not talking about the date in the filename, which might be the date it was replaced as iTunes Library.itl.)
11.1.5 would probably be a better choice, but only if a 32-bit Vista user has a library backup with a date modified that falls between the release of 11.1.5 (Feb 26) and 11.2.0 (May 15). Unfortunately my most recent backup was too new, and the second-newest was much older. Another thing: NonnoAl stated at the top of page 4, "I had the same problem on my 64 bit Vista system when I was on iTunes 11.1."
I will certainly not buy a new OS in order to improve compatibility with recent versions of one free app! If Apple continues to call this app "iTunes for Windows" then it should be compatible with the security features in all Windows versions that Microsoft still supports. It's not like I'm still running XP!