Hmmm, sounds like some sort of Windows 7 ownership, access control (permissions) issue - but why would it happen in DragDrop and not in Add Books
Make sure that 'you' have full control permissions over
- The folder where the book is,
- The Calibre library folder
- Calibre's internal stuff in \Users\<logonuser>\AppData\Roaming\calibre
Heres a Tutorial (Vista and Win 7 are the same) on Ownership & Permissions
https://www.vistax64.com/tutorials/6...ship-file.html
To take ownership of the folders, here's a One-Click gadget
http://www.sevenforums.com/tutorials...-shortcut.html
If that fails, try turning UAC off
If that fails - Hmmm, ditto if it works
BR