Wikipedia:Reference desk/Archives/Computing/2011 April 16

= April 16 =

"Blue screen of death"
I recently had a computer that blue screen of death-ed. It froze and then completely erased Windows from the system. It is currently on the way to the manufacturer to have the hard drive replaced. With that in mind; I was wondering if there is something, specifically, that I should do to prevent this from happening to any more computers? I intend to install some virus software, but that does not always work. Are there any clues as to whether or not a website is infected or not? Sumsum2010 · T · C 04:53, 16 April 2011 (UTC)


 * Only go to websites you know and trust ? StuRat (talk) 05:05, 16 April 2011 (UTC)


 * For a safer browsing experience, I recommend starting by using firefox with the 'no script' plug-in . SemanticMantis (talk) 05:58, 16 April 2011 (UTC)


 * Well, Linux is famous for being safe from many types of attacks and Ubuntu isn't hard to use even for a newcomer. The feasibility of switching to Linux depends a lot on what you're going to use the computer for - office work, Wikipedia/web browsing and software development are easy with Linux, but if you play games that have problems with Wine or really need to use MS Office or Visual Studio or anything, or just are reluctant to switch OS, it's better to not switch, in which case I recommend the advice given earlier. Zakhalesh (talk) 06:12, 16 April 2011 (UTC)
 * You could try use Norton Safe Web, which lets you enter a website and show whether there seems to be anything bad in it. However, common instinct is obviously very important in stopping maculious malware. General Rommel (talk) 07:01, 16 April 2011 (UTC)


 * Far from being a malware problem, the obvious explanation is a simple hard drive failure. To protect yourself from that kind of catastrophe, a good backup policy is recommended.  Astronaut (talk) 10:42, 16 April 2011 (UTC)


 * 1. As Astronaut wrote, back up your data frequently. If possible, back it up automatically to a 2nd hard disk or even a 2nd computer system, or via a service like Mozy that backs up your data offsite.  This will give you a way to save your data from either a hard disk failure or from a malware attack.  It is useful to adopt the mindset that when it comes to hard disks, it's not a question of "whether" the hard disk will fail, but "when".  2.  To reduce the damage malware can do, set up a user account with no administrator rights on your computer, and use that account habitually.  Do not use the administrator account unless you have to (to install software, for example).  This makes it harder for the bad guys to get to your system files.  3. This should be obvious, but don't download software unless it is from websites you know and trust.  Comet Tuttle (talk) 20:31, 16 April 2011 (UTC)

Picasa web video download problem solution failure help request
Hi everyone. If you upload a video to picasa web, It doesn't seem possible to download it again directly and I'm looking for a workaround. I am using firefox, macosx 10.5.8 and someone advised me to type "about:cache" in the address bar and find local cache files. Well, there's a file in there that has the right datestamp, and is about the right size. I've tried renaming it .flv and .mvi, but quicktime won't play the video. Any advice? Robinh (talk) 05:09, 16 April 2011 (UTC)
 * I'm a little rusty on OS X, but I think this may give us a clue. Open up the Terminal application (it's in Utilities by default, I think).  Type "file" and hit the space bar, and then drag the file into Terminal.  Its path should appear.  Then hit enter.  What does it say?  Paul (Stansifer) 13:45, 16 April 2011 (UTC)
 * Hi Paul. Thanks for this:

slug:~/Desktop% file flowers.flv flowers.flv: XML 1.0 document text slug:~/Desktop% But I'm n wiser. Any ideas? Robinh (talk) 20:20, 16 April 2011 (UTC)
 * Weird. I don't think there are any XML-based encodings of video (although you say it's the right size, which suggests that it's a terrible encoding of something large into XML).  Well, maybe try the same thing, but use "head" instead of "file" (to view the first few lines of text).  Paul (Stansifer) 22:51, 16 April 2011 (UTC)
 * OK here goes:

slug:~/Desktop% head -20 flowers.flv &lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"&gt; &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt; &lt;head&gt; &lt;title&gt;Cache entry information&lt;/title&gt; &lt;style type="text/css"&gt; pre { margin: 0; } td:first-child { text-align: right; vertical-align: top; line-height: 0.8em; } &lt;/style&gt; &lt;/head&gt; &lt;body&gt; &lt;table&gt;&lt;tr&gt;&lt;td&gt;&lt;tt&gt;&lt;b&gt;key:&lt;/b&gt;&lt;/tt&gt;&lt;/td&gt;&lt;td&gt;&lt;a href="http://v9.nonxt4.googlevideo.com/videoplayback?id=2a4fbdbfdf362628&amp;itag=35&amp;begin=0&amp;len=2147483647&amp;app=picasa&amp;et=INVALID&amp;el=INVALID&amp;ip=0.0.0.0&amp;ipbits=0&amp;expire=2879698237&amp;sparams=id%2Citag%2Cip%2Cipbits%2Cexpire&amp;signature=70140B912E84A0D591150CCC617870859341BF37.5EA1AF515C9CA9B25C5C81459693638705DDD039&amp;key=ck1"&gt;http://v9.nonxt4.googlevideo.com/videoplayback?id=2a4fbdbfdf362628&amp;itag=35&amp;begin=0&amp;len=2147483647&amp;app=picasa&amp;et=INVALID&amp;el=INVALID&amp;ip=0.0.0.0& amp;ipbits=0&amp;expire=2879698237&amp;sparams=id%2Citag%2Cip%2Cipbits%2Cexpire&amp;signature=70140B912E84A0D591150CCC617870859341BF37.5EA1AF515C9CA9B25C5C81459693638705DDD039& amp;key=ck1&lt;/a&gt;&lt;/td&gt;&lt;/tr&gt; &lt;tr&gt;&lt;td&gt;&lt;tt&gt;&lt;b&gt;fetch count:&lt;/b&gt;&lt;/tt&gt;&lt;/td&gt; Robinh (talk) 01:31, 17 April 2011 (UTC)


 * Perhaps this is obvious at this point, but the file in question was some kind of HTML/XML file linking to the actual file. If you click on the link created above (the googlevideo.com one), it'll download the FLV to your hard drive. (I like flowers in my garden, too.) --Mr.98 (talk) 18:27, 17 April 2011 (UTC)
 * Thank you! But I'm still missing something here.  The file I gave the head for above, was about 43MB, which matches the origincal AFAIR, and the file that I've just downloaded was about 7MB (and won't open with quicktime anyway).  Just to check, you meant clicking on "http://v9.nonxt4.googlevideo.co..."?  Robinh (talk) 19:16, 17 April 2011 (UTC)


 * The link goes to a FLV (Flash Video) file, which is what Google Videos and YouTube and etc. convert videos to. It's a smaller file size (and less quality) than the original. It's all you can download from the web, usually. If you want to view FLV files on a Mac, download the Perian plug-in for Quicktime. --Mr.98 (talk) 04:35, 18 April 2011 (UTC)
 * (OP) OK, thanks for this. I have downlowaded Perian, and can see it in my preferences pane (a red penknife), but Quicktime stills says that flowers.flv is not a movie.  What do I do to get it to work?  Probably something obvious, but I read the redame.rtf and it didn't say how to make use of perian.  Best wishes, Robinh (talk) 07:27, 18 April 2011 (UTC)
 * Are you using Quicktime X or Quicktime 7? Perian only works with Quicktime 7 (which is the fault of Apple, not Perian — Quicktime X, for no reason that I know of, does not support any third party plugins). You may have to re-download Quicktime 7 (link). Perian more or less works after you install it (if it is on the preference pane, it should be installed), so my guess is that it has to do with Quicktime. (It works fine on my machine, with Perian.) --Mr.98 (talk) 19:04, 19 April 2011 (UTC)

Art of Computer Programming
Go Go Gadget Donald Knuth's assembly language simulation software (ability to simulate other assembly languages appreciated). Thank you! Zakhalesh (talk) 11:39, 16 April 2011 (UTC)


 * MIX and particularly MMIX list implementations, including simulators. -- Finlay McWalter ☻ Talk 12:02, 16 April 2011 (UTC)


 * Thank you. Zakhalesh (talk) 12:03, 16 April 2011 (UTC)

How does AT&T ban third party apps on the Android?
Dear Wikipedians:

I was just flabbergasted when I read that AT&T bans third party apps on the Android. I mean, how are they able to do it? I always thought of Android as an open platform where I can browse the web, find the app I like, and just download and install it. None of AT&T's business. So how does AT&T do it?

And also, to raise what maybe an unpopular question here: wouldn't the US be somewhat of a hypocrite applying double-standards, when it accuses China of censoring online stuff, when major companies like AT&T and Apple are doing just the same things to their customers right in the U.S.?

70.31.154.4 (talk) 17:42, 16 April 2011 (UTC)


 * From what I understand AT&T only allow you to install applications via the Android Market. On Android under Settings menu -> Applications there's a checkbox for "Allow unknown sources" and unless that is ticked you can only install from the market. As such I suspect that AT&T have simply customised the software for their handsets and removed that option. This doesn't really stop anyone from rooting their phone and installing apps that way or in turn installing a custom ROM which has normal functionality though.  ZX81    talk  17:51, 16 April 2011 (UTC)
 * The second question doesn't have anything to do with computing, but it's a very common category error. Freedom of speech means that the government doesn't make certain speech acts illegal.  It doesn't say anything about the kinds of platforms-for-speech people may create.  AT&T is legally free to make a phone network where it's against the terms of service to, say, criticize AT&T, or speak in non-limerick form, etc.  In practice, a government may see fit to pass laws that prevent abuse of this kind of thing (which can be a danger with monopolies), such as network neutrality.  But it's a matter of legislation to figure that stuff out (what counts as a common carrier-like arrangement, and what doesn't), because most people really, really don't want a principled rule that, if you relay something that someone says, you have to relay everything that anyone says.  This would, for example, make things like removing vandalism on Wikipedia and comment moderation on blogs illegal, and perhaps the act of gathering together any community of like-minded people. Paul (Stansifer) 22:48, 16 April 2011 (UTC)

Thanks. I am a lot more clear on this subject now. L33th4x0r (talk) 15:24, 17 April 2011 (UTC)

1 connection per second
I am looking for a way, on Windows 7, to limit internet traffic from all programs running on the computer collectively (firefox, wget, IE, etc) to just one connection per second. For example, say example.com only allowed 1 connection per second, and returned an error if it detected more than 1 connection per second. Five requests to example.com are made at the same time (2 from Firefox, 1 from Internet explorer, and 2 from wget) and thus they all get an error. Instead, I would like some way to take those 5 or more connections and make them wait and do each request one by one. Is there a setting in Windows which can achieve this, or does anyone know of a program (like a proxy server or something) that can do this? Setting each program individually to only use one connection per second is not sufficient as collectively they still use more than one connection per second. It is very important that each connection is dealt with and not closed or given an error from the remote server. 82.43.89.77 (talk) 18:01, 16 April 2011 (UTC)
 * You could do it with a proxy server but you probably want to throttle bandwidth rather than connections. Browsers will usually open several parallel connections to get the images on a page.  69.111.194.167 (talk) 07:01, 17 April 2011 (UTC)
 * Any good suggestions for easy to use proxy server programs on Windows 7? 82.43.89.77 (talk) 16:18, 17 April 2011 (UTC)

Whizz with vector files?
There's a request for help at Graphic Lab/Illustration workshop which some readers of this desk may be able to assist with. Ta! ╟─ Treasury Tag ►  high seas  ─╢ 18:51, 16 April 2011 (UTC)


 * I'm uncertain whether I'm looking at the right thing, because I can't read the text. Is this the image you're talking about? (Faithfully copying the text will be difficult, too, for those who don't know what the characters should really look like. Is it Tamil?)  Card Zero  (talk) 23:11, 16 April 2011 (UTC)
 * Yes, that's the image. The Tamil actually comes out fairly clearly if vectorised in Inkscape, it's more the actual crest which I'm having trouble with... ╟─ Treasury Tag ►  pikuach nefesh  ─╢ 07:57, 17 April 2011 (UTC)
 * I had some success using a pixel art scaling algorithm before tracing the bitmap in Inkscape. Now I just have to do the ovals and lettering. Guess I'd better put a note on the Graphic Lab page too. Card Zero  (talk) 11:04, 17 April 2011 (UTC)

C# compiling
Hello. I am very new to programming. I have been playing around in C# and would like to test out my programs. I wrote one in Notepad++ and saved it to my Desktop. In command prompt, I tried to use Microsoft Visual C# 2010 Compiler to compile my .cs file. I entered  and it returned   I tried again with the complete path of my file and got the same results. What I am doing wrong here? Any help would be greatly appreciated. BurtAlert (talk) 19:01, 16 April 2011 (UTC)


 * Maybe you haven't enabled file extensions yet, and the file is actually named Welcome.cs.txt? If that is the case, http://www.fileinfo.com/help/windows-show-extensions.html might help. Unilynx (talk) 20:09, 16 April 2011 (UTC)


 * Nope, just checked, it's definitely Welcome.cs BurtAlert (talk) 23:03, 16 April 2011 (UTC)


 * Make sure your command prompt is in the folder where this file is (if you type 'dir' in the command prompt, you should see your file). Or, type in the full (absolute) path to the file. I don't know what the default folder the command prompt opens to (in whatever version of Windows you're using), but it's probably not to the desktop. Invrnc (talk) 01:06, 17 April 2011 (UTC)


 * Try doing a "dir" followed by the full-path file name, exactly as you entered it before. This will tell you if you have the wrong slash or some such problem. StuRat (talk) 01:23, 17 April 2011 (UTC)


 * Ah, thank you very much guys. I put it in the same directory as the command prompt and it worked! BurtAlert (talk) 01:40, 17 April 2011 (UTC)

StuRat (talk) 22:56, 17 April 2011 (UTC)

Firefox Sync
I cannot access my account in spite of having reset my password about three times, in one instance with the same password. And my Sync secret phrase is correct. What the hell is going on? —Preceding unsigned comment added by 24.189.87.160 (talk) 21:14, 16 April 2011 (UTC)


 * Have you looked at their troubleshooting page? If that doesn't help, there is a link to a support forum at the bottom - you are probably far more likely to get help there than here. 81.98.38.48 (talk) 14:28, 17 April 2011 (UTC)