CD-ROM users often want to be able to set the annotation drive. This cannot be achieved if the index files (ISYS.IX? and ISYS.CFG) reside on read only media, as the annotation drive setting is stored in the ISYS.CFG file.
Publishers can also determine the location for the annotations by typing the AnnotationDrive=PATH command in the ISYS.CFG file or pass it via the command line. For information about this and other command line parameters, please refer to Command Line Parameters.
It should be noted that an AnnotationDrive setting in ISYS.CFG will take precedence over that in ISYS.SET. If you want to set the annotation drive via any of the above methods, be sure there is not an AnnotationDrive setting in ISYS.CFG on the CD-ROM.