Wikipedia:Reference desk/Archives/Computing/2014 February 28

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February 28

Transferring files to a new machine

I just bought a computer and I want to copy some files from an older computer to the one I bought. Under the "Start" menu I choose "Getting started" and then "Transfer your files" and then I see "Welcome to Windows Easy Transfer". Among other things, this tells me that "When the transfer is done, you'll see a list of what was transferred[....]" WHAT? I don't want to have some unknown forces decide what to transfer and then notify me after the fact; I want to decide what files to transfer. Why would that not be presumed? If an actual human behaved that way toward me, I'd consider him or her very rude at best.

What's the best way to do this without being treated so abusively? Michael Hardy (talk) 01:25, 28 February 2014 (UTC)

Click on the Advanced selection and you can choose the files and folders. --  Gadget850 ^talk 01:51, 28 February 2014 (UTC)

Is that something I would see _after_ I start Windows Easy Transfer? Michael Hardy (talk) 02:08, 28 February 2014 (UTC)

This Windows Easy Transfer may tell more. Bubba73 ^{You talkin' to me?} 03:19, 28 February 2014 (UTC)

Or you could get a flash drive, use windows explorer to drag and drop them from the old machine onto the flash drive, then plug the drive into in the new machine and drag and drop them. Or send an email to yourself with the files as attachments, or if you have them on a lan copy the files to a shared folder see Shared resource. Dropbox (service), google drive and other similar cloud base services is yet another way. Old school ftp is a nice way if one computer is linux or a mac these have servers which can easily be switched on. --Salix alba (talk): 06:54, 28 February 2014 (UTC)

This is a nice tutorial on WET. --  Gadget850 ^talk 23:45, 2 March 2014 (UTC)

"Installing" MiKTeX2.9

I managed to use a USB drive to move some files over from my old computer to my new one. I copied the folder called "TeX" and some .tex files and things that go with those including .pdf files, and I copied the folder called TeXworks. I am able to click on a .tex file and immediately I see the editable .tex file and the pdf. And I am able to edit and save the .tex file. But when I try to compile it, I get something saying I need a "TeX distribution". I copied over the whole MiKTeX2.9 folder. What is there in a "TeX distibution" that wouldn't be there? Michael Hardy (talk) 05:32, 28 February 2014 (UTC)

Copying the folder is not enough. MikTeX has a setup wizard that you need to run in order to install it on your target system. See http://miktex.org/howto/install-miktex. Looie496 (talk) 15:16, 28 February 2014 (UTC)

Is it enough to copy the folder and then run the setup wizard, or do I need to do another download? Michael Hardy (talk) 18:21, 28 February 2014 (UTC)

Creating a functional LaTeX installation can be tricky (it used to be much harder). The thing to remember is it's not really a "program" or "application" in the traditional sense, right? There's any number of scripts, processors, distillers, graphics drivers, etc. All those pieces have to know the file paths to where the other parts are, and the apropriate settings may well be different on the new machine. I would recommend doing a clean, fresh installation (from a fresh download of the installer). Having another TeX (/texmf, really) tree involved could break things. Only move over your document files (.tex, .aux,.bbl, .bib etc). If you added any packages to your old installation, I'd add them fresh to the new install as well. SemanticMantis (talk) 18:38, 28 February 2014 (UTC)

To further clarify, the "TeX distribution" is the engine, which does the actual compiling, as well as things like fonts, packages, and many other pieces and parts. MikTex is acting as a front end, an IDE(...of a sort), and a GUI. You can in principle install an distribution of your liking, then make your front-end play nice with it. But, in the modern day, that is madness, IMO :) Most of the modern front-ends (e.g. MikTeX, TeXshop, others) are designed to install their own TeX distribution, that is already set up right. Do it the way they intend, and you should be fine. SemanticMantis (talk) 18:47, 28 February 2014 (UTC)

Thank you. I'll download MiKTeX again. Michael Hardy (talk) 19:43, 28 February 2014 (UTC)

Substituting Transistors on Electronics Project

I'm trying to build a simple transistor circuit for my Basic Stamp, and I can't get it to work. The part list provided by the manual says to use a 2N3904 transistor, but since I didn't have one, I used a 2N3866. Could this be the problem? The circuit is supposed to turn an LED on and off by writing high or low to pin 8 of the Stamp, and right now the LED is always on. Thanks! OldTimeNESter (talk) 15:13, 28 February 2014 (UTC)

Lots of things could be the problem, but from the information provided, we can't know for sure. For a simple, slow application like blinking an LED, any NPN transistor should do the job. You can probably even get by without a transistor at all, and directly drive a tiny amount of current from the microcontroller's GPIO pin. But there's the risk of drawing too much current; and there's the risk that the Basic Stamp doesn't have internal protection circuitry to handle short-circuits without suffering permanent damage. That's why the manual is trying to educate you: you're trying to build "the world's simplest" single-transistor buffer circuit. (Even though you probably don't need it - the Basic Stamp is an educational toy in addition to being a practical engineering tool - and its designers want to train you in proper design for future projects you work on - where the circuits are less robust, or the currents are closer to the safety-limits of the device!)

In practice, the hardest part of working with a single-transistor buffer circuit is making sure you have the correct bias voltage. Do you have a multimeter to check that? Nimur (talk) 17:11, 28 February 2014 (UTC)

Ah... perhaps BASIC Stamp is what this is all about... in case anyone else was wondering. Astronaut (talk) 18:05, 28 February 2014 (UTC)

They do look quite different transistors, 2N3904 has hFE of 100[1], but 2N3866 has hFE of 10.[2] This might affect the the circuit as you will need a greater current flowing from base to emitter to produce the same current from collector to emitter. You might need 10 times as much current to get it to switch.--Salix alba (talk): 20:50, 28 February 2014 (UTC)

Thanks, that's what I was thinking. I bought a 2N3904 and now the circuit works. OldTimeNESter (talk) 13:13, 3 March 2014 (UTC)

What if Google fails?

Are there contingency plans to replace it if it can't deliver anymore? Would the daily life the affected? Many people seem to use Gmail not only for private matters, but also for business stuff. At least in the case of non-US governments, have they thought about the possibility? That would be similar to the GPS dependence: many redundant system had to built, just in case it's not there. OsmanRF34 (talk) 18:22, 28 February 2014 (UTC)

There are dozens (at least) of search engines out there. Google is the most popular - but you can get search results from Yahoo, Microsoft's Bing, and so on and so forth. The dependence on gmail is much more serious...but there are other services that people could switch to. Google maps can be replaced with MapQuest. Vimeo could replace YouTube...I think that every one of Google's services have other providers who offer similar things. That's not to say that there wouldn't be disruption if Google suddenly vanished - I'm sure there would be months of chaos and it might take years for the Internet to fully recover.

Personally, I have my own email server so my account is @sjbaker.org - but I also have a gmail account for the convenience of using Google+ and for my Android phone & tablet. But my gmail address redirects to my regular email address - which is the one that I tell people to use - so if gmail "went away" suddenly, there would be almost no impact on my email. I wish more people would do that - but there isn't much that can be done about it.

SteveBaker (talk) 01:41, 1 March 2014 (UTC)

I have my own domain but use Google Apps for my email meaning if Google really did die I would lose my email address temporarily. Google killed off the free version of Google Apps for new users but there must still be a bunch of legacy customers like me. And of course there are also those who pay as well as Google Apps for Education and non profits. The education program at least seems to have had some success. Of course any service you use, even a service you manage yourself has a risk of failure. It's just the number of user affected that varies and for a service you control yourself, your ability to do something directly about it. (And in reality, a massive service like Google probably has less chance of failure than most smaller services.) Nil Einne (talk) 14:14, 2 March 2014 (UTC)

I should mention that you can of course have a backup MX record that isn't Google (or whatever) although I'm not sure how many bother to do this. E.g. aucklanduni.ac.nz does not according to an nslookup. For that matter you can use Google Apps for your backup MX according to my searches. Of course, as our article mentions the primary purpose for backup MX is really for temporary outage. While I guess there's nothing stopping you using them for the case of your host disappears completely, I'm not completely sure how many, even those that do it for Google Apps, do it under this assumption. Nil Einne (talk) 13:46, 3 March 2014 (UTC)

Converting djvu (with text) to pdf (results in an image)

How can I convert a djvu file to pdf and keep it as it is, with layout, searchable text and the like? So far, the results have been either a pdf composed of images (but perfect layout) and much bigger than the original. Those online tools wouldn't be a possibility since I need to convert big files. A hack like importing it into a program that deals with djvu and exporting a pdf would be also a possibility. Windows or Linux, all solutions welcome. OsmanRF34 (talk) 18:29, 28 February 2014 (UTC)

It looks like the most powerful tools come from DjVuLibre, at http://djvu.sourceforge.net/. Looie496 (talk) 18:53, 28 February 2014 (UTC)

Why did my computer shut down?

Twice in the past several weeks, the second time on Wednesday, I got a blue screen saying my computer had to shut dwon to protect itself. The first time I was in the middle of typing an email. Wednesday I had just pushed the power button to turn the computer off. Both times I got the message that Windows did not shut down normally, and I was given several options. I suppose if I wanted to see an error message or details to explain what happened I could have chosen to do that then. Or maybe the specific error message was onscreen when the screen was still black and white with no way to use the mouse, and I was in too big a hurry to get back to what I wanted to do (Wednesday, rejoin the real world) to bother to look.

When I turned on the computer today, I got a message that Windows was looking for a solution to the problem that had caused the computer to shut down. Is there any way to see what it found, if anything? I also got a message with a yellow triangle in the lower right corner about finding solutions to problems, but when I clicked, the list of problems did not include anything from after 2013.— Vchimpanzee · talk · contributions · 19:25, 28 February 2014 (UTC)

The blue screen is the Blue Screen of Death. Check the article for its multiple causes. OsmanRF34 (talk) 20:37, 28 February 2014 (UTC)

There's nothing specific to my particular software, but it did say the error message appears on the blue screen. Which is obviously gone.— Vchimpanzee · talk · contributions · 22:06, 28 February 2014 (UTC)

This is what I would do. I would download and install Microsoft Security Essentials, which is a free application, and run a FULL scan. It might take hours. Then (but not necessarily in this order) I would go to Start==>Control Panel==>Programs==>Uninstall a program and take a look at the programs that are running on your machine. Some of them may not be necessarily running but they just sit there. The programs are listed in alphabetical order. Go down the list and check them all. The program source (author, publisher) is there in the second column. Where it is Microsoft Corporation, you can leave that alone. Find suspicious names. Google them on the web and see what people are saying about them. If people are screaming that this must be malicious software, uninstall it. This seems to be a sure way to get rid of the suckers.

I had a frightening experience a couple of months ago. I tried to download some innocuous software, not games, not anything vile, I believe it was just an Adobe flash or similar. When I installed it ads began popping up in the middle of my browsers. I tolerated it for some time, then did an investigation, ran security checks - nothing, went into the list to uninstall and found something suspicious. So, I killed it. Another option is to go to the Task Manager and see what is actually running on your machine at any given moment in time. Some of that is pretty revealing. You have to work on it. Takes time. --AboutFace 22 (talk) 17:08, 1 March 2014 (UTC)

If you are an administrator (or perhaps even if you're not), you might check Event Viewer. Go to the Administrative Tools in your start menu or Control Panel and click Event Viewer. Check under Windows Logs in either Application or System around the time the error occurred and you may be able to see the log/what caused the issue. - Purplewowies (talk) 20:54, 1 March 2014 (UTC)

This answer on the Microsoft support forum gives information about how to retrieve and read the dump files created when windows bluescreens. Not sure how much useul information you'll be able to get out of them though. MChesterMC (talk) 10:54, 3 March 2014 (UTC)

Link to our page: Microsoft Security Essentials. You might try Malwarebytes and/or Spybot – Search_&_Destroy too, if MSE doesn't find anything. - ¡Ouch! (^{hurt me} / _{more pain}) 06:53, 5 March 2014 (UTC)