Wikipedia:Reference desk/Archives/Computing/2008 November 24

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November 24

bad sectors on hard disk

I have a 250 GB hard disk, purchased one year earlier .It has bad sector more than 70 % ,is any method to recover these bad sectors. —Preceding unsigned comment added by Khubab (talk • contribs) 00:38, 24 November 2008 (UTC)

The usual method is to mark the bad sectors as unusable and continue to use the rest. That's what Scan Disk does. I doubt if there's any cost effective way to actually fix the bad sectors. StuRat (talk) 00:47, 24 November 2008 (UTC)

been a while; i remember that you could rightclick on a disk in the my computer explorer window, and one of the options undr properties/tools was error checking; and one of the options for check now was attempt to recover bad sectors or attempt to recover data or some such. of course, that depends very heavily on what type of disk/controller it is. 70% bad sectors is so extreme that either something is so screwed up that it's unfixable, or else it's so screwed up that it's easily fixable. (like thehead has moved .000000001 micron sinc it was formatted and reormatting it will fix it but not get the data back). lots of free and for $ software out there that addresses the problem, can't say what's good or bad myself. Gzuckier (talk) 01:53, 24 November 2008 (UTC)

Do you mean recovering the data on the bad sectors or being able to use those sectors again? In the second case I wouldn't bother. A 250 GB hd costs way too little to be bothered rescueing the hd. Unless you're really low on cash and don't value your time too highly, buy a new one. It could easily have had a head crash or something, in which case it might completely die on you pretty soon anyway. If you want to rescue data, you're likely in more trouble. If fsck or scandisk or the like has had it's way with your hd, then the data might be completely lost (they're not designed for rescueing data). Impossible to tell without more info (not that I would know if I had the info, mind you). As for rescue software, I've used one such program to rescue data on a memory card that I accidentally formatted, which worked brilliantly (although slowly). But this is a hd with bad sectors, and that's a different story. If the data are essential, you might consider taking the hd to a data recovery company, but that will probably cost you several hundred €. Although the diagnosis will be cheaper (tens of €), but if it's for free it's likely not a reliable company that might do more harm than good. If it's not worth that much, but still worth an effort, you might start by reading data recovery. If only so you can ask your question here in a more informed and informative way. DirkvdM (talk) 09:09, 25 November 2008 (UTC)

Film scanner problems

Hi There My father has purchased 3 film/slide scanners over the last two years, all of which have failed in one way or another. The latest one, which I just installed for the second time, now simply refuses to start when I click on the desktop shortcut. the power light is on and I truly installed it correctly per the manual. My question is not about this specific scanner, VuPoint, but about this type of hardware in general. What are the common causes of this type of failure, that is, new hardware just not working? If I rule out that the equipment and/or software is just crap, possible, as he buys cheapo stuff on ebay, are there settings or other things that can be adjusted to increase the odds that these products will work correctly? He has a Windows XP system and lots of other devices plugged in via USB. i am thinking of getting him a good mid-range ($300-400), brand name slide scanner such as Minolta, Canon or Epson for Xmas but don't want to do this if its going to crap out because of som,ething in his system. I realize this is a little nebulous but perhaps someone has some ideas that will increase the odds of this working. Thanks! —Preceding unsigned comment added by 64.234.6.82 (talk) 01:14, 24 November 2008 (UTC)

I don't know much about slide scanners, but general troubleshooting tips include power cycling the device (turn on/off, unplug/plug back in if necessary), trying a different USB port, trying a different USB cable, and trying it on a different computer if possible. You can also check in the Device Manager to see if the device shows up and/or has any information about problems it's having. If he really has a LOT of other USB devices connected, you might try disconnecting a few of them to see if they've been drawing too much power. Indeterminate (talk) 04:03, 24 November 2008 (UTC)

change in how wikipedia displays in my browser

I have access to wikipedia via two machines. on the one i am using to write this, nothing has changed lately, but on my other machine, all of a sudden the display has changed; the top line with links to my user page, talk, preferences, watchlist, contributions, etc. no longer appears and those links are now way down near the bottom of the page; similarly the links on the normal left hand bar are also just way down the page; also, the popup i get by hovering over a link (with a link to the link, talk page, etc. plus the first chunk of ext) doesn't work on the other machine thougjh it still works on tjhis one; i can't remember what makes that link work or where it lives, i looked in my monobook.js file but all i see there is lupin's antivandal tools... i didn't change anything on the other machine, but of course IT is always "improving" it without telling us. so anyway, what got busted that I can fix? tia.Gzuckier (talk) 01:45, 24 November 2008 (UTC)

Does the other machine run a different browser version? If the style sheets are not loaded this strange behaviour is the default that will happen. You may just have to shift-reload the page to fix it up. WP:HD will be the place to find people who can answer this question. Graeme Bartlett (talk) 05:07, 24 November 2008 (UTC)

Interrupts in the human brain

In the human brain, which interrupts are maskable and which are non-maskable? NeonMerlin 05:28, 24 November 2008 (UTC)

Why would computer interrupts be equatable with anything to do with the human brain? I don't see people deciding they need to eat food and suddenly completely dropping everything they were doing before, eating the food, and then resuming from where they left off. Or anything of that nature. The brain is a complex neural network of sorts, it's not procedural, so there's no simple equivalent to an interrupt.

As for "masking", that also depends on what you exactly you want. A certain neurotransmitter/toxin could cut a mental process off; many can be controlled at least somewhat 'consciously' or 'unconsciously' as well, depending on one's psychological state. If one expects to be shouted at, for instance, they may not startle. It's still not exactly equatable with interrupts. -- Consumed Crustacean (talk) 06:00, 24 November 2008 (UTC)

good question. interestingly, pain, which is a serious interrupt, is quite maskable; mammals (at least, haven't observed others) can ignore injuries suffered in a fight or even serious play which would really stop them in their tracks if they were doing nothing; then it hits them later. and of course, hunger and thirst, but i don't know how interrupty they are, more on the line of a long term warning flag. Gzuckier (talk) 20:15, 24 November 2008 (UTC)

What is command use &mmo in foxpro?

What is command use &mmo in foxpro? —Preceding unsigned comment added by Tanejask du (talk • contribs) 08:49, 24 November 2008 (UTC)

How to enabled ENUM in existing DNS.

How to enabled ENUM feature in existing DNS.Please provide the step by step procedure. I need DNS should support NAPTR.I want to use it in windows,linux.And one more thing is

—Preceding unsigned comment added by Ashis xor (talk • contribs) 09:15, 24 November 2008 (UTC) 

• Telling us which kind of software your using on the dns server would be helpfull. - Esurnir (talk) 18:56, 24 November 2008 (UTC)

NAS+USB drive

I have a home theater system that I can attach a memory stick or hard drive via USB and play MP3s. I would like to be able to share a hard drive between my music system and my PC so that I can add or delete files without unplugging the drive. I'm looking for an external drive or enclosure that will support NAS and USB at the same time. Every one that I have found so far will disable the USB port when the network cable is attached. --—— Gadget850 (Ed) ^talk - 16:49, 24 November 2008 (UTC)

• The problem you are facing is that USB is an interface that permit to have an entire control on the hard drive, it encapsulate SCSI/ATA commands for the hard drive which are of the form of "write this buffer to block 123" "read block 432" etc. A NAS on the other hand is created by an operating system where you send commands of the form "write this buffer to file blabla.doc at position 699" the operating system managing the orders at which the ATA command will be read, manage conflicts between two clients trying to access a single ressource, etc.

Now, an operating system connected to a usb expect to have entire and full control over a hard drive, it doesn't know "filenames" and even if the os of the machine detected that the os of the home theatre is trying to access a zone of data that is currentely being modified, denying access to that zone would be interpreted by the os of the home theatre as a hardware defect in all probability. Now I expect someone to tell me there is a workarround for such things, but to the extent of my knowledge it is simply too complicated to emulate a logical hard drive to an operating system while operating on said hard drive. As such the NAS partition and the USB one will be separate/can't be activated on the same partition at the same time. Esurnir (talk) 19:19, 24 November 2008 (UTC)

Figured it would be something like that. For about the price of a NAS drive, I can buy a low end PC and hook it directly to my system and run jukebox software for audio and video. --—— Gadget850 (Ed) ^talk - 14:55, 25 November 2008 (UTC)

How would you secure OSPF on windows server 2003

I'm currentely following MCSE course and we are currentely learning how to setup the routing on a windows 2003 server.

While doing the lab and testing ospf, I discovered (because I ran wireshark during the whole lab) that the ospf packets sent by windows server 2003 -broadcasted- packets, with the password in the header. Save the case where all routers would be on the same switch and using the same password and that no one could sneak into either switch or router, this security level is for me a heinous crime against every computer security principle I've yet to learn. When I asked the teacher about it the answer was "don't use windows server as a router, move to cisco" which was for me slightly unsatisfactory. Imagining I got other clients joining the physical network uppon which ospf packets get exchanged, how could I do to make those exchange more secure ?

Would I need to setup vpns between each and every routers ? IPSec ? Esurnir (talk) 19:19, 24 November 2008 (UTC)

Weird TV colors

My TV started displaying weird color tints a few days ago, and now it's settled on a permanently blue-green tint (I think). Once or twice it was a reddish tint. Will this be expensive to repair? Thanks. Imagine Reason (talk) 19:36, 24 November 2008 (UTC)

Assuming it is a CRT television and not an LCD or Plasma flat-panel, it sounds like you lost the color part of the signal and you are just getting the black and white part. But, I'd have to see the television to see if what I think you are describing is what you are seeing. Regardless, the labor cost for repairing a television is often more than the cost of a new television. I just checked and I can get a brand new TV from Walmart for $130. I know that two of our electronics places charge a minimum of $150 in labor, regardless of the problem. If you need a $200 flyback transformer on top of the cost of labor, you'll be upset that you didn't just buy a new TV. -- kainaw™ 19:49, 24 November 2008 (UTC)

a relatively frequent (i.e. i've seen it happen) problem with crts is the death of one of the three color guns, which skews the picture color to the opposite direction, obviously. once in a while i've been able to fix it with a good smack, not always. if the picture tube is gone, of course the tv is a goner. Gzuckier (talk) 20:26, 24 November 2008 (UTC)

The general rule of thumb is to replace if the cost of repairs would exceed 50% of the cost of a replacement. A brand new item will typically have a 12 month warranty minimum, a repair might only be guaranteed for 3 months. Exxolon (talk) 20:08, 24 November 2008 (UTC)

You've almost certainly already ruled this out, but... if your watching an external source (like a DVD player or set-top box), is it connected securely, and have you tried another cable. With the SCART connector in particular, if its not in quite right it can lead to some of the RGB pins not connecting properly. Cheers, davidprior (talk) 20:17, 24 November 2008 (UTC)

another rule of thumb is that the expected lifetime of a color TV is about 10 years. (on the other hand, my house is filled with Sony trinitrons which refuse to die, going all the way back to those rotary tuners). however the impending end of analog TV changes things, (in addition to the switch to flat panel tvs); depending on what your signal source is, you might not actually newed a TV at all, with tuner etc; if you're hooked up to cable/dvd/vcr, like me and everybody i know, all you really need is a video monitor and audio system, with no tuner. all i use those trinitrons for now is as video monitors, although the old ones have to get fed via the tuner on channel 3/4./ Gzuckier (talk) 20:22, 24 November 2008 (UTC)

This is definitely a TV problem, as both the cable and Wii look off in the same way. All the reds are not gone, but I'm pretty sure the red gun is somehow not working right. Imagine Reason (talk) 01:21, 25 November 2008 (UTC)

Have you moved any loudspeakers nearer or further away lately? If so, it could be a faulty degaussing circuit in the TV.--GreenSpigot (talk) 03:13, 25 November 2008 (UTC)

It's possible that it needs degaussing - most TV's do that automatically when you turn them on - but if you are one of those people who leaves the TV on 'standby' 100% of the time - then maybe it hasn't 'naturally' degaussed itself for years! So you might try turning the thing on and off at the power outlet a few times (wait at least 30 seconds after each time). A few older models have either a degauss switch - or (rarely) an option to degauss in the on-screen menu somewhere. Generally though the consequences of a 'gaussed' screen (I'm sure that's not the right term!) is that some areas of the screen are screwed up and the others are OK...but it's easy to try and if you've lived a good life and donated $20 to Wikipedia recently - you might get lucky. Sometimes you need to do it several times to get the full benefit. If the degaussing circuit in the TV is indeed busted you can actually get degaussing guns - you used to be able to rent them from stores that sold TV's - but since almost all TV's have their own built-in degaussing coils, that probably won't get you anywhere.

But it sounds much more likely that you have a bad red gun...and sadly that's probably the most expensive thing to fix in the entire TV.

SteveBaker (talk) 18:34, 26 November 2008 (UTC)