Wikipedia:Reference desk archive/Computing/2006 September 16

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September 16[edit]

Exploded CD[edit]

Peice of Exploded CD
Exploded CD

My CD disk literally exploded inside my CD drive. I had just installed Windows XP and from the kitchen heard a brief a crash that sounded a small water glass or mirror breaking on the tile floor. A popup window was saying XP had installed a driver for new hardware it had found and needed to restart. When I looked at the computer the CD drive bay was stuck open about 3/4 of an inch. I tried to close it but it would not budge so I removed the drive from the computer. As I turned it sideways I heard pieces of the CD moving inside.

What is going one here??? I thought that CD's were supposed to last at least 20 years. This is a Verbatim brand DataLifePlus Recordable CD. The silver coating on top of the plastic is also cracked in many places and peeled away. Some of the adhesive is still active and many flakes are now "glued" to other pieces of plastic. Is this a Verbatim problem or what? The coating on all of my old Verbatim 8 inch floppy diskettes disintegrated many years ago as well. Adaptron 11:39, 16 September 2006 (UTC)

Wow. I'd say those CDs are defective, all right. I'd avoid using them. If you haven't already destroyed the CD player you likely will if you try to use those again. I'd contact the company and see if they will give a refund. If you give them a batch number and they know that was a defective batch, they may very well take them back. If they are a recent purchase (which somehow I doubt), you could try returning them to the retailer. StuRat 12:04, 16 September 2006 (UTC)
No they were as I recal purchased around 2000 but the real issue is the trust I placed in a CD and the data that was lost. Since I've had a similar experiience (disintegration) with Verbatim 8 inch floppy disk I'll stay away from Verbatim. Adaptron 13:52, 16 September 2006 (UTC)
This is actually not unheard of, though the Wikipedia article isn't very elaborate. —Bromskloss 13:48, 16 September 2006 (UTC)
Good. I'll add links to these images to that page. Adaptron 13:54, 16 September 2006 (UTC)
MythBusters explored this a while ago and found that normal CDs will not shatter in a conventional CD drive (the spin speed isn't high enough). However, the stresses on a spinning CD are considerable, and a defective CD (a small crack, a weak spot, manufacturing error...) could shatter under normal operation. — QuantumEleven 19:55, 16 September 2006 (UTC)
It only takes a very small amount of flutter in a 40x CD-ROM drive to create a whole lot of friction, and it's pretty easy for that to happen if your CDs are poorly balanced (you can actually slightly unbalance CDs by writing with some types of ink on only one side of the CD) or if the CD-ROM motor is starting to get old. Once the fluttering starts (you can usually hear it, though CD-ROM drives often flutter with no concequence) a CD can explode with even the slightest bump, or like Quantum said, a small crack or weak spot. These things used to be very common back when people were trying to manufacture rediculously fast CD-ROM drives, though it seems that everybody has settled for about 40x nowadays.  freshofftheufoΓΛĿЌ  07:35, 17 September 2006 (UTC)
Wow. That's some abuse right there. --Proficient 08:53, 17 September 2006 (UTC)
No joke. I had no idea this could occur! It's rather amazing. --Fastfission 13:49, 17 September 2006 (UTC)

What does this mean?[edit]

In our tar (file format) page, we have this line of code here:

tar -cf - file_to_pack1 file_to_pack2 ... | gzip -c > packed_files.tar.gz

What does this mean, particularly the second hyphen on the line? This to me means something like this:

tar -cf
Make an archive of compressed files
Well, I don't know what this is.
file_to_pack1 file_to_pack2 ...
All the stuff I want in my tarball
pipe the output of the tar thing
gzip -c > packed_files.tar.gz
to our nifty gzip program which compresses the output and sends it to the file packed_files.tar.gz

More or less right? But I have a feeling these things need to be a bit more precise. Help appreciated :-) --HappyCamper 12:12, 16 September 2006 (UTC)

The -c flag tells tar to create an archive, and the -f flag tells it where to put the results (or more precisely, which tar archive to use---the same flag is used to select the source when extracting files). The trick is that the -f flag requires a filename as an argument, and giving the filename "-" selects the standard output (or the standard input, whichever is appropriate). Also, unix commands are expected to parse multiple flags together, so that -xyz is equivalent to -x -y -z. This is why the GNU long options such as --create are preceded by two dashes. 13:48, 16 September 2006 (UTC)

ANSWERED -> computers field[edit]

i am starter in the computer field. how should i decide my direction?

Don't. You are just starting. How could you possibly have any idea what your favorite area of computing is? Dabble in everything until something seems enjoyable enough to stick with for a long time. --Kainaw (talk) 19:33, 16 September 2006 (UTC)

I'd say look at what else you like for a clue:

In addition, there are many other fields where computer usage is critical. These include jobs in the medical, legal, scientific, and humanities fields.

StuRat 05:53, 17 September 2006 (UTC)

Indeed. Get to know the field first then narrow it down slowly. What are you interesting in right now? --Proficient 08:53, 17 September 2006 (UTC)

Firefox doesn't recognize Windows Mediaplayer plugin[edit]

When I try to run streaming Windows Mediaplayer videos in Firefox, it says I'm missing a plugin. When I set it to automatically finding it, it can't find one. Reinstalling WMP 9 (for Windows 98) has fixes a file that didn't run previously in IE6 due to a missing codec, but when I installed it, I didn't get any plugin options for Firefox. How do I get Firefox and WMP to work together? =- Mgm|(talk) 16:31, 16 September 2006 (UTC)

This page might be able to help. --Mitaphane talk 21:33, 16 September 2006 (UTC)

Is there a way to alter the WinXP welcome screen?[edit]

So I can, for example, make the user images larger or change the background colour/image?

I don't know about changing the SIZES of the user images, but it IS possible to change the background image as well as text and locations. On my laptop, I've used Logon Loader to change it to a POKéMON-themed one.
There's a selection of login screens at, and I believe there are links to programs that can be used to create your own if you don't like any of those (or want something unique). --Pidgeot (t) (c) (e) 18:22, 16 September 2006 (UTC)


Whats a free program to use to make an avi movie of image slideshow and maybe add some music? 18:25, 16 September 2006 (UTC)

I think iMovie offers something like that, Windows Movie Maker(for Windows) probably offers something similar as well. --Mitaphane talk 21:30, 16 September 2006 (UTC)

Windows recovery CDs[edit]

Yet another Windows/Linux question: I am taking the plunge into Linux (Ubuntu, to be specific). Currently, my PC has a single hard drive with one partition on it running Windows XP. I am planning to wipe it (having first backed everything up), reinstall Windows, partition the hard drive, and then install Ubuntu on another partition to set up a dual-boot system. However, I only have the recovery disks for Windows from the manufacturer of my PC (Acer). If I understand correctly, these rely on a hidden partition somewhere on my hard drive in order to reinstall Windows. My question is, can I inadvertently delete/damage/modify this hidden partition, and so prevent myself being able to reinstall Windows after I format the disk? What steps or precautions do you recommend I take to prevent this from happening? I don't feel like shelling out another 100 Euros or so for a 'retail' version of Windows, given that I already have a copy on my system. Thanks in advance for any advice! — QuantumEleven 20:05, 16 September 2006 (UTC)

The first thing I'd do is verify that there really IS a hidden partition using Disk Management. If there isn't one, then it's no problem, and you can go ahead and do what you want.
If there IS a hidden partition, however, you'll likely want to save it, or you could end up messing things up badly. If there's an option to create CDs that can be used instead of the hidden partition, you might want to do that.
That being said, even if there is a hidden partition, there's always the option of only messing with the Windows partition, doing so will leave the hidden partition perfectly safe and working.
Additionally, you should note that if the only reason you're formatting is to partition the drive, there's no need to do so - tools like Partition Magic and ntfsresize can be used instead. I've used the latter one when I tried installing Linux in a dual-boot setup on my laptop, and it works very well (as long as you follow the instructions). --Pidgeot (t) (c) (e) 20:33, 16 September 2006 (UTC)
My thinking exactly, GPartEd that comes on the Ubuntu live CD should be able to handle that fine. No need to remove and reinstall windows Oskar 02:59, 17 September 2006 (UTC)
Ah, I hadn't thought of that! I checked and, yes, there is a hidden partition which shows up in Disk Management. I'll now go ahead and repartition with GParted, we'll see how ot goes. Thanks very much for the help, you people saved me potentially a lot of trouble! :) — QuantumEleven 09:07, 17 September 2006 (UTC)
Recent Acers ship with an application (which I think is called Acer System Recover) which is really a rebranded Norton Ghost. One of the functions that has is to allow you to burn the recovery partition to a DVD; you should certainly use that before undertaking any repartitioning efforts. But really, given how cheap a modest sized hard disk is now, I'd just install a new drive and put Linux on that. Then you don't need to mess around with the Windows drive at all. -- Finlay McWalter | Talk 09:12, 17 September 2006 (UTC)