Recordable/Rewritable Discs

  Southernboy 14:14 20 Oct 2005

I seem to have got myself in a muddle over the above. I was under the impression that CD-R could be used once only and CD-RW could be used many times. The same being true of DVD discs.

I am now told that recordable discs can be used more than once. To test this I bought a 5-pack of DVD+R discs and backed up my two main files which only used 25% of the disc. The next backup, I inserted the same disc. I then got a message asking me if I wanted to create a "multisession disc" - so far so good. I clicked "yes". It then read the disc and reported that there were already files on the disc (I knew that) and did I want to replace them. I selected "yes" and then was told "the index was out of bounds" (whatever that means) and the backup then proceeded. Checking the disc, I noticed that only the most recent backup could be read. Presumably, the previous files are still in the disc, but cannot be accessed? The disc now appears to be 50% written.

At the next backup I selected not to replace the existing files and, apart from not receiving the "index" warning, everything proceeded the same. The disc is not about 75% full, but only the most recent backup is accessible. Do I assume that this method should only be used if you don't mind losing previous backups? Do you lose previous backup files even if they are not included in the next backup?

How does this vary with DVD+RW? Are previous backups accessable? Does it overwrite all files or only those that are selected in the next backup set?

Sorry for this long query, which I hope I have clearly explained. I never had this facility until I bought this PC, and a spot of clear guidance on how to use the DVD writer on my PC would be very welcome. I have been rather put off RW discs by the many comments that they don't last and are subject to problems.


  DieSse 15:15 20 Oct 2005

What you have found in your tests is perfectly correct.

CD/DVD R disks cannot be erased and written to again - that's the real difference. You can always continue adding to an unfilled R disk until it's full (as long as when writing it you don't CLOSE it. If you CLOSE it then it gets converted to a format just like a CD-ROM that cannot be added to).

CD/DVD R/W disks can be used in the same way as R disks - but with the added feature that they can be completely erased and used again. But they DON'T work like a hard drive (or a ZiP drive) - files don't get overwritten when updating, the new version gets written and the old one disappears from view.

Also - confusingly, there are different ways of writing to CD/DVD disks, which may produce different effects - it depends a lot on which software you use for backing up /writing to them.

  DieSse 15:23 20 Oct 2005

click here If you're using Backup4all there is a version upgrade that addresses the index out of bounds issue.

  Confab 16:05 21 Oct 2005

I not sure I understand this bit "But they DON'T work like a hard drive (or a ZiP drive) - files don't get overwritten when updating, the new version gets written and the old one disappears from view"

What ablout packet writing sofware like INCD which lets you use your RW's just like a hard drive or Zip Drive? Files DO get overwritten.


  DieSse 17:19 21 Oct 2005

Files DO get overwritten.

No they don't - read here how packet writing works click here

  DieSse 17:46 21 Oct 2005

Sorry - take foot out of mouth and apologise.

WinXPs packet writing does not let you delete material. And if you packet write to a CD-R, you can't of course delete. But using In-CD and Direct-CD it appears that you can.

I have to confess I don't use these now - only the WinXP one.

  Confab 17:56 21 Oct 2005

No need to apologise I just wanted to make it clear for Southernboy.

Confab :-)

  Southernboy 20:42 21 Oct 2005

as I am still confused. I will re-read this before I come back.

As a matter of interest, how do you CLOSE a disc?

I am using the OEM version of Pinnacle which came with my new PC. I have been recommended to dump it an buy Nero 6.0, but I thought I ought to understand how it all works before I take any action, expecially as I have been warned that Pinnacle can be hard to uninstall.

I did try DVD+RW discs when I first bought my PC. Looking at those discs, it does not seem to be possible to delete anything and further backups seem to have added rather than replaced my files. At first sight, the result appears no different to the DVD+R discs. I thought it would simply overwrite what went before but, visually, the "playing side" appears to be almost full, even though my backup is less that 600Mb.

Thank you for your patience.

  ade.h 21:21 21 Oct 2005

The principle advantage of a CD-RW or DVD/RW is not so much its re-writable layer, but the fact that it can be multi-sessioned. This is packet-writing. If you want to replace a previous session rather than add to it, you need to erase the unwanted files or the entire disc, whichever happens to be most convenient.

As for CD-R and DVD/R discs; I don't know how easy it is in Pinnacle, but Nero makes it simple to choose between a write-once single-session recordable disc and a multi-session disc that will not be finalised and thus can be added to (but not over-written, of course) at a later time. Nero handles this through options in the writing wizard that appears right at the start of a session.

  ade.h 21:27 21 Oct 2005

Note that for packet-writing to re-writable media, the built-in Windows XP utility is the simplest choice. It is drag-and-drop in nature and disc erasure is a one-click job. Nero relies on InCD for this task, as mentioned above but I haven't bothered to use InCD since Win XP was first introduced and InCD failed to work properly with it.

  Confab 13:53 22 Oct 2005

I don't understand this bit "The principle advantage of a CD-RW or DVD/RW is not so much its re-writable layer, but the fact that it can be multi-sessioned. This is packet-writing"

Packet-writing is where you use your CDRW/DVDRW like a big floppy disk. You don't need to open any sessions. You just format the CD/DVD and away you go. Just drag & drop & erase at your leisure. I use Incd for this.

Perhaps someone could clarify this for me.


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