can't delete a strange system file

I found a strange hidden system file inside an ordinary folder that's located in my D drive (D:\DownoadZ)
I showed the hidden files and also the system files, and I noticed there was a strange file (0 KB) I haven't seen before (I used to check my system for some reason).
However, this file is called "CA63EB6H." so it has no extension. Where I know there is no important system files supposed to be in that folder, I tried to delete it. But I always get a message says "cannot delete file: cannot read from the source file or disk".
Moreover, that file has no owner and can't be read so, I couldn't take the ownership (it has no security tab). And i can't be renamed or even deleted on the save mode. Also, I've tried to use move at boot to delete it but got nothing.

Somebody may say it's not a big deal! yeah it's not a big deal while the file is harmless.
But if anyone has a "guaranteed" idea please share it.

Who is Participating?
victornegriConnect With a Mentor Commented:
It could be that since you have no permissions and aren't the owner of the file, the file will not show it's true size and will display as 0 bytes.

Try these:
command line permissions to give full control to Administrators:
cacls CA63EB6H. /g user:"administrators":F

or you can try "rmdir /s downloadz" from your D:\  and then recreate the downloadz folder.
Is it a folder? Move On Boot can't delete folder.
Try Killbox
*Select the "Delete on Reboot" option.

If you're using XP Home, you have to be in Safe Mode to see the Security tab in order to change permision.
sniper038Author Commented:
>>Is it a folder?
!! who said that?

>>If you're using XP Home
it's xp pro
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sniper038Author Commented:
>>Is it a folder?
!! who said that?

>>If you're using XP Home
it's xp pro
Can you see the Security tab for other files? If not, you may have to disable Simple File Sharing:

 Win Explorer -> Tools -> Folder Options -> View -> Un-check "Use Simple File Sharing..."
you can always go the long way...

use recovery console (boot the original windows cd and select 'R' to get into the console,

navigate your way to the directory the file is in and change its attributes like this...

attrib -r -a -s -h CA63EB6H

you should then be able to delete the file like this

del CA63EB6H
Get process explorer (google for it) and check what is holding the file open.
Once you install/run it, do a find for the file name.
You can close the lock that the system has on the file, provided it is safe to delete this file.
You can delete it from DOS:

Start --> Run and type CMD <Enter>
del *.*

If that doesn't work then do this before del *.*
attrib -h -s -r *.*

>> Get process explorer (google for it) and check what is holding the file open.

Process Explorer will not tell you that.  WhoLockMe, however, will.  Download at

That will tell you what has a hold on the file.  NOTE: I am not recommending deletion; see below.

>> CA63EB6H

That sounds like a temporary file name to me.  It is not worth worrying about.

I come from the school of thought that is "If it ain't broke, don't fix it."  Nothing is broke now, but that file exists for a reason.  Everything is working fine now, but will it be if you delete it ?  Fine, you may say "how could deleting a file of zero size do any damage" but do you really know that it is of zero size ?  How do you know Windows is not lying to protect itself, so to speak ?  I seem to remember a colleague telling me about files of zero size that are something to do with the way windows handles partitions, but cannot remember exact details.

Don't delete it, because the bottom line is that you don't know what you are doing, no disrespect.

Windows partition information wouldn't be stored in a folder called "DownloadZ". I agree that it's a temporary file but I don't think it will affect anything by deleting it.
>>...but I don't think it will affect anything by deleting it.

Fair comment.  I just think that the questioner would kick himself if deleting this screwed up the windows installation or something else...

If you cannot delete it in safe mode, which is usually the well-trodden path for problems like this, then there is a good chance that you are simply *not meant to delete this file*.  

Why fight it ?
sniper038Author Commented:
man it's a matter of "Principle" ;)

im trying some of the suggestion now

"But if anyone has a "guaranteed" idea please share it."

There are no guarantees with windows -- otherwise Gates would be broke.

Those type of files are made by the system when you do a disk copy or something similar that needs a buffer on the hard disk to complete.  They are random combos of number and letter, almost always 8 character, no extension.

When you shut down and reboot, the file will be freed.  It is because you did something that needed a buffer file on the hard disk to complete.  When it is freed, look at it, it will usually be a diskette image or something like that.  Check your path and you might find you use D:\ for a TEMP drive on some application, hence that is where temp files go.
I you don't care about the effects of deleting a locked file, then download this freeware progrm:

Install it with all the standard options.  After it is installed, go to the file you want to delete and right click it.  Select "Unlocker".  When  this opens, there will be a drop down box.  Select "Delete".  This will delete the file regardless of what programs are currently using it.  Just in case though, make a system restore point before you try this.
my turn.
Often times these lttle 0klb files  may come from a program that required to log its activity.
Like a cab file or a data file, I apprciate it may not be of any importance but simply annoying.
What I  do with these files to delete them that is:
open task manager, processes> look down to explorer and end it.
your desktop will dissapear, using the file> new task run in task manager then> browse go to your file in D drive, r/click it  and delete it.
Hopefully it work.
Then go back to new task run type in explorer press enter. desktop back.

sniper038Author Commented:
thank you all.
I've tested all suggestions, but non worked out :(

i believed in the windows repair method but i couldn't access the file.

for your info, the file is not being used by anything, I've used many tools to make sure of that.
the problem is that the file is not owned by anyone. moreover, the security tab is not available for this particular file. so, no one can take the ownership!. we need to think of away where we can take the ownership of a file that's not owned by anyone and has no security tab.

*note: the file is not harmful but it becomes a dignity matter ;)
Try erasing it with this program (Eraser 5.3) @
If it is a 0 byte file (truly 0 bytes, not just "0 kb") then just leave it -- it cannot do any harm.  A zero byte file cannot be even a virus (unless masking size from OS) -- so merete s comment above is probably close to the situation.
Since the Operating System has trouble finding the file for deletion, it is possible that the file may be the result of a corrupted Master File Table.  Try running error checking on your hard drive.  Go to My Computer.  Right click your hard drive and click Properties.  Select the Tools tab and then click Check Now... Check both boxes and then click start.  It will say that it needs exclusive access.  Say yes to running it at startup.  Restart your computer and it will take atleast an hour to scan everything.  Once it finishes, try to delete the file.
It sounds just like a socket file, that is, a file used to stream data through a temporary file, called a socket.

It would make more sense to describe it were it a Linux box.  There are numerous socket type files on your system, most under the temporary directories.  If you can right click and get the properties, it should tell you what type of file it is.  Socket and temporary files often are zero byte files because they are just a path through which streams of data pass.  Downloading, for example, would use a socket file to take the data from the ftp, feed it through a socket file, and temprorarily store it in a randomly named file.  When the download completes, the temporary file is copied to its real file name and the temporary file should be deleted.  The socket, however, may remain open.  Many Windows temp files remain open as sockets for the temporary streaming and movement of data from one place to another.  The sockets permissions belong to the Operating System and not even an Administrator may have sufficient permission to delete them, or, the deletion will be access denied, and/or, it will simply be regenerated as fast as you delete it.

You could try the same thing with various files in you temporary directories and note that they too cannot be deleted or they will instanlty be regenerated.

Here is a typical tree structure for UserData temporary folders:

<drive>:\Documents and Settings\<username>\UserData\YVQY8YWG

note the seemingly random file or directory name YVQY8YWG

A socket is basically a buffer, as scratchyboy suggests.

What do the properties say about it?
sniper038Author Commented:
access denied for the first suggestion

"bingo" for the next one: rmdir /s downloadz

great job guys
Glad it worked out! Thanks for the "A"!
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