I.D. Key

The so-called I.D. key is a number (in hexadecimal format) of 8 characters length, with a hyphen in the middle, like this one:

Using the I.D. key for assigning passwords is useful because it is different for each computer, so a password generated using the I.D. key will be only valid in the computer with that I.D. number. In this way your users can't share their passwords with others, neither register the publication on a second computer.

You can get the I.D. key from different places that can be selected from a drop-down list at the bottom of Protection tab, as shows the image below:

• Hard disk volume number: The I.D. number is taken from the hard disk Volume number, which is assigned to the disk when it is formatted (1).
• Hard disk serial number and volume number: Here you get an unique serial number, because the real serial number is combined with the Volume number (1,2). We do not recommend using this option, see footnote 2 below.
• Hard disk serial number: The I.D. number is taken from the hard disk serial number. Because it is hard coded onto the hard disk, it does not change ever, although the disk were partitioned or formatted, but if two computers have just the same hard disk model and brand, the number may be the same. To get an unique number you may select any of the other options (2). We do not recommend using this option, see footnote 2 below.
• Windows identification number. The I.D. key is read from Windows itself. If Windows is reinstalled it may change.

(1)

The I.D. number will change every time the disk is formatted, partitioned or the file system changes from FAT32 to NTFS (which is used in the later Windows version since Widows 2000).

(2)

Accessing the hardware under Windows is not as straightforward as it was under DOS, so the real disk serial number may not be retrieved under some unusual hardware combinations and the system may freeze. We do not recommend using this option getting the I.D. key from the hard disk real number because may be 5% of the systems may freeze. Be aware that users running Windows 2000, 2003, XP or Vista will need to run the ebook with Administrator rights to allow it to read the hard disk serial number.

Read I.D. from disk C forces the viewer to read the number from that location instead of reading it from the disk on which the program is running.
If your executable ebook runs from a CD-ROM and this option is not checked, it will read the CD-ROM serial number.