Multisession allows your CD-R or CD-RW drive to continue writing to CD-R or CD-RW media that already has information on it as long as its session was not "closed". (This feature is for data and MP3 CDs only, not audio CDs).
When you insert a new piece of CD-RW media into your CD-R drive you'll be able to write to it as normal.
If you insert a previously written to CD-RW disk, you'll see, in the right-hand corner of the burner window the word, "Imported."
"Imported" means that (1) the CD is in Data or MP3 mode, and (2) you can write more data to the disk before closing it.
When you choose to append to CD-R/RW media the true size of the inserted media will be shown, including any existing data. Blue indicates existing data (mainly for use with multisession burns), green/red indicate space to be added to the media. Green is used when the proposed additions fit in the remaining free space. Red is used when the proposed additions will not fit on the disc. If red is present simply remove some of the files to be burned.
After you've perfected the data list to be burned, click the Burn button to begin.
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