Wikipedia:Reference desk/Archives/Computing/2011 October 7

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October 7

If I have an infected XP Pro x32 with the heur zero day threat and want to dual boot it with either an XP Pro x64 or a windows 7 x64, will the virus pass over.

Hi to all,

I have an XP Pro x32 bit operating system & it is infected with the Heur zero day threat virus. I am in the process of geting it fixed up through PC Tools. The Anti-spyware program people who brought out the Spyware Doctor. It is not fixed yet, but I wanted to dual boot this operating system with a Windows XP Pro x64 bit or maybe with a Windows 7 x64 bit operating system instead. My question is, is it safe to dual boot with either of these operating systems or will the Heur Zero Day threat virus migrate to the newer windows x64 bit partition containing the operating system within the same hard drive disc & infect that also. Also which operating system out of the two would be the least likely one for the Heur Day Zero Threat to migrate to if it can. I should add though, that I would rather use up my windows XP Pro x64 bit operating system first. I would like to do this before I return to work next week if I can as I have nothing else to do while I am off work. It has already been a week that PC Tools has had my problem in their hands. I would like to hear from people that have knowledge please & not just hear say thank you.

   124.189.33.41 (talk) 01:08, 7 October 2011 (UTC)GAZ.  — Preceding unsigned comment added by 124.189.33.41 (talk) 01:06, 7 October 2011 (UTC) 

Hope to hear from someone soon 124.189.33.41 (talk) 00:18, 7 October 2011 (UTC) GAZ. — Preceding unsigned comment added by 124.189.33.41 (talk) 23:56, 6 October 2011 (UTC)

I'm not familiar with the "heur zero day threat virus", but the only way it could cross over is if you accessed the infected system's files from the uninfected system, or vice versa. Windows might attempt to give you access to filesystems connected to the same hardware by default — what you'd want to do is tell it not to. http://webchat.freenode.net/?nick=heurZeroDay&channels=##windows ¦ Reisio (talk) 00:20, 7 October 2011 (UTC)

What software told you that you have "Heur zero day threat virus"? That does not sound like a virus name that would be used by any reputable virus scanner. Most of the free "virus scanning" software that you will find online is actually a scam that will report fake problems in an attempt to get you to pay money for a useless removal tool. -- BenRG (talk) 02:43, 7 October 2011 (UTC)

In Firefox my Adobe Reader buttons (above the pdf-file in view) don't work!?

When I open a webpage with combined html and PDF content, then the Adobe Reader buttons (save, print etc.), in top of the PDF-frame of the webpage, don¨t work. While, strangely enough, the "goto page#" box and the "zoom level" box, just beside the frozen keys, they are accepting and handling input correctly.
I have Firefox v7.0.1,
Windows7(64)Home and
AdobeReader v10.1.1
I have tried uninstalling and reinstalling Acrobat Reader but the problem persists.
Could you please help me get things back to working order?
--Seren-dipper (talk) 00:12, 7 October 2011 (UTC)

Pages on a particular site, or any site? ¦ Reisio (talk) 00:22, 7 October 2011 (UTC)

Any PDF ;-(     I just discovered that the same problem occurs with plain PDF files (not just the html+pdf web pages). For instance: http://www.viewsoniceurope.com/uk/product_pdfs/lcd/27/E-VX2753mh-LED.pdf
--Seren-dipper (talk) 00:39, 7 October 2011 (UTC)

Sorry for being vague, but I remember having in-browser PDF-reading problems with Firefox a while ago — I think it was related to very large PDFs — and my workaround was that whenever there was a link to a PDF file on the Web, I would right-click that link and choose "Save As", then after downloading the whole PDF, I would launch plain old Acrobat and load the PDF, without involving a Web browser at all. Comet Tuttle (talk) 18:24, 7 October 2011 (UTC)

Yes, that is a good workaround when dealing with plain PDF files, but not when a URL is to a "pdf+html" because then Acrobat Reader is unable to open the resulting saved file.
Regarding file size: My problem, with Adobe buttons not working inside Firefox, is just the same for a small, one page, PDF file.
I refraze my question in the subsection "Preferences limiting..." following below:
--Seren-dipper (talk) 02:44, 8 October 2011 (UTC)A

Preferences limiting what a Firefox plug-in is allowed to do?

(This is a continuation of my above question ("Adobe Reader buttons don't work in Firefox")
Does Firefox have some preferences setting (or something in "URL://about:config") that may limit what a Plug-in is allowed to do, and which may be the reason why the Adobe plug-in buttons (save, print etc.) does not work?
--Seren-dipper (talk) 02:44, 8 October 2011 (UTC)B

Help identifying TV.

Hello, I was wondering if anyone has the same TV as I do, also wondering what exact TV it is, so if anyone does know please tell me and please tell me as well what the best settings are for playing a Blu-ray movie on a PlayStation 3 with that TV. Specifications below:

1. It's a Sony

2. It's a 32" Inch

3. It has 1 HDMI input (my Video 6)

4. It has 2 Composite video inputs (those are my Video 4 & 5's)

5. It has a Coaxial input

6. It has some inputs on the right side, an RCA input (Yellow, White, and Red inputs) and an earphone input to move the audio to the input (this ismy Video 2)

7. It has 2 more RCA inputs (Video 1 & 3)

Thanks to anyone to helps me identify the exact TV model.

66.138.72.16 (talk) 01:13, 7 October 2011 (UTC)

I've got a Sony Bravia TV too, isn't there a menu option that gives you the model number? Number of inputs won't be enough information to guess the model number.. Vespine (talk) 05:51, 7 October 2011 (UTC)

Every TV I've ever had, has had the model number on the back, usually on the same plate that specifies the serial number, input voltage, etc. Unless it is really old, the official Sony website for your country will let you download user manuals and specification sheets for your TV model. Astronaut (talk) 09:29, 7 October 2011 (UTC)

Alright thanks guys, I'll go look around for it. I'm just trying to figure out the best Blu-ray settings for it. — Preceding unsigned comment added by 66.138.72.16 (talk) 11:49, 7 October 2011 (UTC)

This may answer the question you are really asking: You definitely want to use the HDMI input. Comet Tuttle (talk) 18:22, 7 October 2011 (UTC)

Yes Comet Tuttle, I am indeed already using the HDMI. Thanks anyways — Preceding unsigned comment added by 66.138.72.16 (talk) 04:01, 8 October 2011 (UTC)

But at what resolution? My PS3 is broken at the moment, so I can't check, but doesn't it have an option for "Automatically determine settings"? Try that first.

If that doesn't work, personally I'd start at the top and work my way down. First set it to 1080p and see if that works. If not set it to 1080i, then 720p, then 720i. (Here "works" doesn't just mean you have an image. It could be doing some bad down-sampling. Make sure the image isn't distorted or blury, and make sure there isn't an unusual lag or stutter.)APL (talk) 22:49, 7 October 2011 (UTC)

Deleted account

Hi

I have not used my account in a long time and apparently it got deleted. I made my first contribution in 2006 with the username Nil0, I have tried to make a new account of the same name but it is not allowed since it resembles an account with the name Nilo too much. Since I were able to create my account in 2006 I am sure I came first ;-)

Could somebody recreate my account?

Regards Nil0 — Preceding unsigned comment added by 77.75.167.178 (talk) 10:12, 7 October 2011 (UTC)

An account on Wikipedia, or some other site? On Wikipedia accounts cannot be deleted, are you sure you have spelled the name correctly? User:Nil0 does not exist but User:Nilo does, have you tried logging into that one? If you want to make a new account with a name similar to an existing one but are prevented from doing so by the system, make an account with any name and then request a name change, or request an account with the name you want. AvrillirvA (talk) 10:54, 7 October 2011 (UTC)

work done in increasing the length of wire by a hanging mass (m)

pls if know about it answer to this — Preceding unsigned comment added by Rohit240819942 (talk • contribs) 13:03, 7 October 2011 (UTC)

Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our policy here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. - David Biddulph (talk) 13:07, 7 October 2011 (UTC)

Consider reading conservation of energy; but you also should conceptually understand that ductile deformation of a wire is a very good example of nonconservative work. Nimur (talk) 16:28, 7 October 2011 (UTC)

To explain that in layman's terms, you might think that the work done in stretching the wire would be equal to the work required to move the weight from the lower point to the higher point. However, this isn't quite true because work is also done generating heat during the stretching process.

But, in a classroom setting, they may want you to ignore the heat. You might do the calculation assuming it should be ignored, but then add a comment that explains why it can't be, to cover you in both cases. See gravitational potential energy.

Incidentally, this Q belongs on the Science Desk. StuRat (talk) 21:48, 7 October 2011 (UTC)

Making a film

Let's try this again, since it didn't work before. About a week ago I posted a complaint about my video editing program: ' So, I wanted to fit a bunch of pictures together to create a short film, like a slide show, but a bit quicker than I expect they could manage, and whilst experimenting with my video editor (avidemux), I found that I could open pictures in that and stitch them together into just such a film. However, if I try to add a picture that is not the only one in the folder, it adds the whole contents of that folder, but with all but the first in the wrong colours, all bright and jumbled up instead. if I move things in and out of the folder one by one, it can only find the last one, so no easy way around that. And now it turns out, if I save it and load it again, it all comes up in the wrong colours anyway, and with all coloured dots over the pictures as well. Meanwhile, even the right colour images are of a rather lower quality than they were originally. '

What I wanted was either 1) someone to give me instructions on how to make this program work the way I wanted or 2) someone to tell me where to find another program that could do the job. What I got was a link to what seems to be a site where someone is explaining their attempt to create a program that can do this, something I doubt I could do myself. I cannot see how that can help, and so still need the answer, with my first attempt now archived, I thought the time has come to try again and see if I get any more helpful results this time.

148.197.81.179 (talk) 15:18, 7 October 2011 (UTC)

If I recall correctly, you are referring to your question on October 1. Reisio linked (without much explanation) to some instructions to an FFMPEG tutorial. FFMPEG is probably the best tool to do what you're asking: it's a command line utility, and it is free software; you can download it from the official FFMPEG webpage - for almost every type of computer and operating system commonly available. The tutorial Reisio linked - Making movies from image files using ffmpeg/mencoder - looks pretty thorough to me; for example, the command ffmpeg -r 10 -b 1800 -i %03d.jpg test1800.mp4 will combine all your JPG images into one output movie file (explained in more detail in the tutorial). Are you having trouble following those directions? Do you need help getting the software running on your system? Are you looking for other software? For example, iMovie for the Mac is able to composite image files into a video file, and has a graphical user-interface.

AVIDemux can also specify input files using a Workbench File, sort of a "project" script; their syntax is specified in the avidemux documentation, Using Project Files. Nimur (talk) 16:26, 7 October 2011 (UTC)

OK then, I just couldn't see where in that link it said what it was or what I should be doing with it, perhaps I just did not read it carefully enough, I will have another look, see if I can work it out. 148.197.81.179 (talk) 21:37, 7 October 2011 (UTC)

Playing a mini-CD on my MAC superdrive

I got a CD in the mail that I want to listen to. I've never seen a a CD this size. I don't have a ruler but laying coins end to end its three (American) quarters and half a penny in diameter. It says on it "CD2/2" and maybe that's the size. Can I put this in my MAC Superdrive? I'm scared to try. I don't have a CD player.--108.27.98.230 (talk) 16:37, 7 October 2011 (UTC)

Is it a Mini CD? They are not compatible with most slot loading drives without an adapter and I wouldn't put it into a Mac. It will probably get stuck if you do. --Mr.98 (talk) 17:02, 7 October 2011 (UTC)

Traffic and number of servers

If following data are right:

   * Google: 1,000,000 servers, 24,000 employees.
   * Facebook: 60,000 servers, 2,000 employees.
   * Microsoft: 220,000 servers, 90,000 employees.
   * Yahoo: 50,000 servers, 13,900 employees. 
   * WK: 370 servers and fewer than 100 employees.

Then how can you explain this huge difference? Wikiweek (talk) 18:36, 7 October 2011 (UTC)

What huge difference are you referring to? Are you talking about servers per employee? If so, here are the numbers in a more straightforward format:

• Google: 1,000,000 servers, 24,000 employees. - 41.6 servers per employee
• Facebook: 60,000 servers, 2,000 employees. - 30
• Microsoft: 220,000 servers, 90,000 employees. - 2.44
• Yahoo: 50,000 servers, 13,900 employees. - 3.5
• WK: 370 servers and fewer than 100 employees. - 3.7

Is this the difference you're wondering about? Dismas|^(talk) 18:41, 7 October 2011 (UTC)

Volunteers. -- kainaw™ 18:42, 7 October 2011 (UTC)

(ec) What exactly would you like explained? Unsourced estimates about the number of computers operated by various organizations differ in magnitude? Nimur (talk) 18:43, 7 October 2011 (UTC)

Is WK meant to be Wikipedia? The reasons for its low numbers overall are pretty obvious — it doesn't make very much money and it relies on volunteers. For the others, you have somewhat different business models at work. Google employs gobs of programmers all working on different things, but mostly within a web niche. Facebook is essentially just one web-based product. Microsoft has gobs of programmers working on gobs of products and uses its servers to do all sorts of business-y things other than websites. I have no idea why Yahoo has so many employees. --Mr.98 (talk) 19:51, 7 October 2011 (UTC)

I think another big diff is that many of those other servers perform CPU-intensive tasks like generating map directions, while Wikipedia mainly just serves up text and illustrations. StuRat (talk) 21:39, 7 October 2011 (UTC)

These data are official and are from WK. They are about the top 5 more visited pages. You see the huge difference in the number of servers to manage the traffic load. The low number of employees of WK is easy to explain: lots of volunteers to do the hard work. Wikiweek (talk) 21:48, 7 October 2011 (UTC)

What's WK? Do you mean WMF? Nil Einne (talk) 21:57, 7 October 2011 (UTC)

Yes, Nil Einne, WK is WMF, you are right. Wikiweek (talk) 22:13, 7 October 2011 (UTC)

The low number of servers is perhaps explainable by the fact that the vast majority of Wikipedia's visitors are (a) not logged in and (b) not editing, so the Squid caches can just spit out a pre-rendered page. Google result pages are dynamic, so they can't do that kind of caching. Paul (Stansifer) 22:04, 7 October 2011 (UTC)

Source is here. Sounds like an explanation. Source here, BTW: [1]... Wikiweek (talk) 22:13, 7 October 2011 (UTC)

Whatt wikipedia.org does't provide (and the other 4 yes): -no dynamic content, adapted to each users -no several GB email accounts -no usual software download, of sometime >100 MB Quest09 (talk) 00:48, 8 October 2011 (UTC)

Hash gathering website - Why

This website : http://www.xdecrypt.com/google-sha1-cd7c-3

Presents hash values of things like logins.... How is that useful ?

I guess there is already some botnet harvesting these things and using them... but in which ways...

85.81.121.107 (talk) 20:37, 7 October 2011 (UTC)

It's a rainbow table (and a good illustration of why unwhitened hashes are suboptimal for password storage). For example, the md5sum of "spaceman" is 91e363cf471a1bce35b3458967a754d7; look that up on the website and it successfully finds "spaceman" for it. -- Finlay McWalterჷTalk 20:48, 7 October 2011 (UTC)

Most websites or systems run by slightly competent people don't store passwords in their databases as plaintext, because if someone grabs the database, they have all of the users' passwords. So they store hashes, and compare the hashes of the entered passwords with the hashes in the database. Well and good, except that with lookup tables (like your site is), you can store up huge lists of hashed phrases and words and then quickly compare that database with your password database, rendering those passwords into their plaintext. The way around this, as Findlay alludes to, is to find ways to increase the difficulty of this sort of thing, like adding a salt to all hashed passwords. If the salt is unknown, then you've effectively gotten around lookup tables altogether; if it is known, then you've just required a re-computing of the whole table. --Mr.98 (talk) 22:40, 7 October 2011 (UTC)