Helping people with computers... one answer at a time.

We'll look at why you might not be able to add files to a CD-R.

I have just burned music files to a CD-R for the first time, 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 files?

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.

"When you burn a CD-R you can elect to leave it 'open' - 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.

Article C2517 - January 10, 2006 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

January 11, 2006 8:11 AM

I know that recordable DVDs have "+" and "-" versions, but I have never heard of such a thing for CDs. Are you sure you haven't gotten the DVD +/- issue confused with CDs?

Leo A. Notenboom
January 11, 2006 4:57 PM

You are quite correct. Did I mention it's all confusing? :-) I've corrected the article. Thanks for catching that.

Andrew Denny
January 16, 2006 11:54 AM

A further point (I'm not sure if it should be a separate question) is the relative longevity of the two types - CD-R and CD-RW. Is one better than another? I save my photos to CD, and I can't wait to bundle up 700mb of photos before I create a CD. I hear conflicting advice on which to use for best archive.

January 16, 2006 9:45 PM

I prefer CD-R, but that's purely based on gut feel. Like you, I find lots of conflicting data. But I do have 20 year old CD-R's that still work. :-)

January 20, 2006 5:40 AM

Why doesn't my driver recognize the CD-R? I can burn a CD-RW with no problem.

January 25, 2006 10:42 AM

I think this question is inline with your topic - however, I'm writing files to CD-RW media to transfer to another system and want to delete the files afterwards. I tried that, but I get a message saying that the folders and file on the CD-ROM are Read Only and I can't delete. I'm just using Windows to delete, is there SW out there that will do what I need? Thanks!

January 25, 2006 1:31 PM

"But I do have 20 year old CD-R's that still work. :-)"

Maybe I missed something, but is this a joke? You have CD-Rs from 1986? I suppose there were CD-Rs out there in some labs somewhere... maybe... but come on!

January 25, 2006 1:38 PM

I was working at Microsoft at the time, and absolutely we had CD-R's. (Not RW, R)

January 25, 2006 1:57 PM

I believe Microsoft may have had some early form of a WORM drive, but it wasn't a CD-R which is what your answer is refering to.

"The characteristics of a recordable CD were specified in the Orange Book II standard in 1990 and Philips was first to market with a CD-R product in mid-1993."
Qouted from :

February 14, 2006 11:58 AM

can tell me how?

March 26, 2006 1:24 PM

I had a cd burned for me over in Iraq. All that it has on it is different airplanes. How do I erase the items? They are all jpg files but the note I get is: 213 items, 1472 is a read-only file. Then it asks if I want to delete it all, I say yes to all and it comes back with: Cannot delete 1472:Files on this CD-ROM drive are read-only. You cannot copy or move files over to this CD-ROM drive.

Is there a way to remove them?

March 26, 2006 1:38 PM

Nope. It's a write-once media. CD-Rs cannot be erased. (But if appropriate, they can be destroyed, of course :-)

June 5, 2006 9:40 AM

why cant i burn cd-r when i got a cd-rw drive

June 11, 2006 8:55 AM

Hi Sir

I just want to know how i can i create CD readonly so no body can take a copy of my data in that CD ?

Thanx alot

June 11, 2006 3:24 PM

If a CD can be read by you, it can be read by anyone. Either you need to encrypt (so that you would have to go through an additional decryption step to use the data yourself), or I'm not understanding your question.

September 15, 2006 6:03 AM

hi i just had a cd-r to which i wrote some files, with multisession open, at a later date again i tried to write another file and an error showed up saying if i write these files the previous files cant b read by ie, i ignored n did write the new file , nw i have this new file but all my previous files r gone!!! hw n where? b coz cd-r is read only hw did the previous files get erased ????????? pls explain....

November 13, 2006 4:45 AM

i am trying to open some video files from my cd-r but i don't know how

November 27, 2006 3:11 PM

sir i just want to know why i cant burn audio files in my cd? (a blank cd for sure)BUt i can write data files to it. May i know what's the reason? do i got virus which affect on cd urning?

Keith Ryan
December 1, 2006 2:32 AM

I make slide shows with roxio or irfanview. I would like to put more than 1 on a disc but cannot save them in a format that allows this. I can only put 1 on a disc burning from roxio or ifanview, is there a solution?

Gay Devoe
December 14, 2006 11:11 AM

Wrote data to cd. Put it back into computer and it tells me read only. I typed new data and it would not let me save to the cd. Why?

Anamie Garcia
December 21, 2006 1:42 AM

Why can't I add files to my CD-R?
December 21, 2006 1:48 AM

why can't I add files to my CD-R???

ken rasheed
March 11, 2007 4:33 PM

I still don't understand how to add files to a

July 29, 2007 2:36 PM

Hey is there anyway i can clear a CD-R??

November 12, 2007 1:02 AM

If you want to re-write, ie. Add more files onto it, I'm pretty sure you need a CD-RW (CD Re-Writable) disk. Most CD/DVD burning programs will allow you to change the settings in order to be able to add further files.

December 1, 2007 12:37 AM

One of the easiest Programms to write CD's; DVD's and add further data etc I have found is Ashampoo 7. All the styles and setting are a simple to read and select .

December 10, 2007 8:14 AM

I liked the answer. its good as you said U tested by writing the discs in two different ways is good.

And from Ur answer I came to know why some of my discs show less size while having more data.

Thanks for Ur answer.

March 11, 2009 2:27 AM

I have choosen mutisession option even then the CD-R is showing the status as closed.

April 13, 2009 6:46 PM

So, now in 2009, is there a CD that you can "add" files to without LOSING anything that's on the CD/DVD??

December 1, 2009 7:20 AM

I've printed out your instruction for burning CD with Windows XP.When I get to properties/recording.The box that shows up does not have the sharing and recording sections at the top of box.Do you know what I'am missing.I've never saved files to CD drive before.Been using a zip drive.But would like to get the files off the zip drive disks to move them to a new computer I have.Which doesn't have a zip drive.

December 6, 2009 5:12 PM

after writing data for cd/dvd when i put the disk in it always says cd/dvd is full and it is not because it is new never used tried other cd/dvd same message need simplified help

John Hill
August 19, 2010 7:49 AM

I read your article on adding files to CDR. I have been adding files to CDR disks since 2004 using XP's CD Write utility with no problems. I don't remember seeing anything about leaving the disk opened or closed. Now in 2010 I no longer can add files to any of these disks. How can I get this functionality back? I have Nero and it won't let me do it either. It says the disks are read-only.

John Hill
August 19, 2010 8:14 AM

This adds to my prior comments. I found that the XP CD Writing wizard uses Roxio software. I checked the properties of the CD drive and found that Recording was not enabled. After enabling recording I found I could add files to CDR's as before. I also didn't see any mention of closing the write session. Somewhere between rebuilding my C: drive and the various Microsoft XP fixes, the record property of the CD Drive got reset.

March 3, 2012 4:04 AM

thnx a lot for the info.
but i wonder can we still enable the open option iff in case we closed it earlier while burning stuff to our cd??
will it work?

August 26, 2012 10:40 AM

please help me ! I received a work cd with pdf files on it which I accessed with a password; I stupidly created a folder giving it the password name and then clicked on " write to cd" and now I can't open any of the pdf files ! What do I do?thanks

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