You can add onto other photos on a CD if you have not closed the CD.

There is an option, usually on the page just before you get ready to burn the CD.

However.......I would advise against this.

Such a CD can only be read by your computer. You can not assume that other computers can read it. Set top players will not recognize it.

Once the CD is closed, there is still a problem if it was written with more than one session. You can not assume that all of the photos can be read by other computers or set top boxes. Other devices/computers may only see the first batch.

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CD blanks are cheap.
You can get name brand blanks for 20 cents.

Put each batch on its own CD.

You can combine them onto one CD later when you get enough collected.

You load the CDs back to the computer and organize them into folders and burn everything at one time. And close the CD with the burner software.

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