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Why can't I open a certain file that's on a CD?


I made a CD of my address book & when I tried open it I got the
following message. “The address book has been locked by another application.
Please close the other application & try again later” I Googled the problem
& I did as Microsoft suggested & made sure the “Read only” box was
unchecked In all address book files. It was. Still no luck. Any help would be
greatly appreciated.

The problem, I suspect, is that there are two types of read-only.

And a program that requires that files NOT be read-only wants it both

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There are two ways that a file can show up as being “read-only”:

  • The read-only flag can be set for the file. Every file on disk has this flag
    and of course it can be either on or off. In Windows Explorer, right click on a
    file, click on Properties, and you’ll get something like

    Properties of Outlook.pst

    This example shows the read-only flag as being set, so this file cannot be
    written to.

  • The file can be on read-only media. ALL files on read-only media
    appear as read-only. And CD-R is a read-only media. The individual property, above, may or may not indicate
    read-only, but because you can’t alter the contents of a CD-R once burned, they’re read-only

“…even after copying the files from CD
to your hard disk, the files will still be marked as read-only.

What typically happens is that a program that tries to use the file will
attempt to open the file and ask for the ability to write to it. If the file is
read-only, for either of the above reasons, that open will fail.

The confusing part is that this attempt to open can fail in ways that are
very similar to the failure that happens if another program has the file open.
The net result is the slightly confusing error message you receive.

So, what to do?

Since the CD will always be read-only no mater what you do, you need
to copy the file or files to your hard disk and open them from

But, naturally, there’s a catch.

When files are copied the program you use to copy them sees that the files
are read-only. Unless you tell it otherwise it “copies” the read-only
attribute with the files. That means that even after copying the files from CD
to your hard disk the files will still be marked as read-only.

But this time, on your hard disk, it’ll simply be the read-only attribute on
the file that has been set. Right click on the file, click on
Properties, uncheck the “read-only” attribute, and
hit OK. You’ll need to do that for each file you copied and/or
need write access to.

Do this

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11 comments on “Why can't I open a certain file that's on a CD?”

  1. Errr Leo, it’s certainly not necessary to “do that for each file you copied and/or need write access to” (i.e. to remove the “Real-only” attribute); one can simply select more files and/or folders and do that only once for all the files/folders together.


    best regards,
    Ivan Tadej, Slovenia

  2. Dear Leo,

    When I burn CDs (RWs) with data files (MS Word) for the first time, everything is fine and I can open the files and work with them. I save the disk to be read on (or be compatible with) all “CD-ROMS.” However, when I try to access the files on the CD the following day, the CD is not recognized. The CDs work fine on other PCs.

    I thought perhaps the CD-ROM wasn’t working, but it works perfectly when I insert a CD that I have not burned, but purchased or one that has been burned by someone else.

    Thanks for your help.


  3. I finally copied and pasted onto an email to myself all the information that was on my CD-RW disk as “read only”. Then when I tried to delete that information from the CD-RW disk, it will not let me delete it. How can I delete what I don’t need anymore on the CD-RW disk?


  5. How annoying this is. I have XP and cd/rw drive and it is maddening that I can’t just copy whatever I want to the CD without big brother watching and putting stops in my way. First I’m forced to put all the files into a temporary spot on my hard drive, and then it will “allow” me to copy but then it makes everything “read-only”. You stated that cd-r is always read only. Is that ALL CD/R’s, RW’s, DVD’s – I’m confused.

  6. Joyce –

    CD-R, DVD-R are writable only once. Once data is burned or written to the -R optical media it is forever-after only readable. No further writing is possible. This is the physical nature of the media and not a plot by the government or “big brother” to take away all of your freedoms.

    Once data is written to the disc there is no method to “delete” or change the data in any way.
    The only way to change or “delete” the data is to physically destroy the disc with methods such as shredding in a paper shredder. Most shredders these days come equipped with the ability to shred optical discs.

    CD-RW and DVD-RW discs, on the other hand, are rewritable and can be burned many times. Data files on those types of discs can be “deleted” in the sense that the files can be over-written with other data. Some DVD-CD burning programs even support “erasing” an -RW disc by writing blank data onto this media but won’t be able to do anything with an -R disc.

    None-the-less, the Windows file system NTFS will still see the files on any optical disc as “read only” because NTFS doesn’t natively support on-the-fly writing to optical discs, the way it does with HDs and USB drives. That’s why we always have to use a third-party software program to burn CDs and DVDs. That’s also why we can’t open a file contained on a CD, edit the document and save the changes. Windows has no mechanism for doing that. The file has to be copied to a non-optical drive and changed from that location, then reburned onto the -RW or to a new -R disc.

    This inconvenience is the main reason I haven’t used CDs or DVDs as backup media for years, since USB drives became available. Thumb drives are much easier to use and far more reliable than CDs plus the capacity for storage is much higher. I even had my data backup USB thumb drive go through the laundry but after I left it alone to dry for 24 hours it still worked and all of my data was still intact. Try doing that with a CD or DVD backup. I would say that using optical media for archiving purposes is a thing of the past.

  7. “[W]hen I tried to delete that information from the CD-RW disk, it will not let me delete it.”

    @Ursula: I can’t delete files, either. I can only overwrite them (on CD-RWs). I think that’s the nature of the beast.

  8. As to the problem of another program apparently using the file – get the freebee ‘unlocker’ which halts all invisible activity related to the file and lets you copy/move/erase/rename it on a HD.
    Erasing/rename/move isn’t possible on a CD-R as mentioned as its set in ‘plastic’ :)

  9. I use USB FlashDrives for some archives, and CD-R’s for others.

    Archives containing files which are expected to be “permanent” and to seldom change, or which are expected to contain fixed or “standardized” versions of certain files — files which I wouldn’t want to change — I’ll put on CD-R’s or DVD-R’s, exactly and precisely because they cannot be deleted or changed once written to.

    Other archives — those which are not expected to be of an “unchanging” nature — I’ll put on an USB FlashDrive, since they have larger storage capacities, are read/writeable, often have faster access times, and can be formatted for NTFS (a thing you cannot do on a CD or DVD unless you use a “virtual drive container”, such as TrueCrypt permits).

    In this way, I get the best of both worlds…      :)


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