Suppose you have a read-only Blu-Ray optical disk drive.
Suppose you put a BD-R blank optical disk in that drive.
What does Windows 7 do?
Answer.  It suggests that you drag files and folders to be burned into Windows Explorer.
All goes swimmingly until you click the Burn link.
Then the drive opens and a dialog box instructs:
"Insert a disc."
"Either the disc in the CD or DVD burner isn't a writable disc or it's full."
"Please insert a writable disc into drive E:."
Well, it happens that drive E: is NOT a burner, so the suggestion that that problem is with the medium is FALSE.
Is it not possible for Windows 7 to detect whether an optical disk drive is capable of burning?
Is it possible for Windows 7 NOT to mislead the end user?

It isn't always obvious that the black thing with the button is or is not a burner.