When relocating case items, Media files require special treatment during the relocation.
Media files are typically much larger than images or other case item files. For this reason, before a relocation is begun you are prompted to choose whether or not to copy these files. In general, if your videos are run from individual CDs there is no need to copy them. If you are copying CDs to a hard drive, then you may wish to copy the files ahead of time to the appropriate directory. By "pre" copying, if you run the relocation feature often you will not need to keep copying the same files.
Since a single Video file may have numerous clips associated with it, it does not make sense to use the Group/ID naming option (otherwise the same video file would copy over and over again). If you choose Group/ID naming, video files will still be copied, however the original naming and path information will be used.