then at a later date tried to add a music file to the same CD-R. I get the
message my disk is closed when I try to add a music file at a later time. Is it
not possible to add files to a CD-R disk after you have already burned
Burning CD-ROMs has gotten easier over time, but it still suffers from some
obscure terminology and odd situations. Add to that
CD-RW (which is quite different from CD-R), and I can easily
understand some confusion resulting.
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meaning that more files can be added to it.”
It depends a lot on the tool you’re using to burn your CD-R. I happen to use
Roxio’s Easy CD Creator, but I’ve heard good things about Nero as well.
You stumbled on to one of the key terms: closed, sometimes also referred to
as “finalized”. When you burn a CD-R you can elect to leave it “open” – meaning
that more files can be added to it. Often case the default is to “close” the
disk, meaning as you’ve seen, that no more files can be added.
When you leave the CD-R open for more files, the disk space is used
slightly less efficiently, and there can be occasional glitches. In
researching this article I burned a CD-R in two sessions; I burned a set of
files and left the disc “open”, and then added another set of files and closed
it. In a command prompt it correctly shows that the disk now has around 650
megabytes on it, however Windows Explorer shows it as having only 298, the size
of one of the two sessions. All the files are visible in both cases.
My approach to burning CDs has always been to collect up “around” 650-700
megabytes of stuff, and then burn the entire disk in one sitting – closing, or
finalizing it. I believe that’s the safest, most compatible approach.
Multi-session CD-R support was added after CD-R’s had started to become
popular, and while it works and is convenient, there’s still a slight risk that
the CD-R might not be readable on all PCs.
And to be clear, CD-R is what’s called a “write-once” technology. Once you
write to it, you cannot erase what’s been written. CD-RW is a
Read/Write technology, meaning that you can write, and erase from the media.
CD-RW uses a different type of media.