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January 23

Wipe harddrive except for OS?

I have an HP Pavilion DV6 with Win7 that I'm trying to sell. I don't have a windows disc. I've googled everything - this doesn't work in my situation. I've been monkeying with the F11 thing for several hours to no avail. I don't think this laptop has a restore to factory default function. There are no restore points. So far I've just uninstalled and shift+deleted everything on the laptop, so it seems maybe good to sell but I know there's still a bunch of my personal stuff lingering.

Is there a program that just wipes every single thing except the OS? The thing's hardly worth anything anyway, if I can't completely wipe it I'll probably just use it as kindling once bonfire season comes around. NIRVANA2764 (talk) 17:44, 23 January 2017 (UTC)[reply]

Without the OS disk that came with the laptop or a restoration partition, you'd have to wipe the entire hard drive and re-install Windows. This would also be the safest option for protecting your personal data. A program like DBAN will securely wipe the disk. As for re-installing Windows, if your laptop has a Windows product key sticker somewhere on it, you can download a corresponding Windows installation disk for that version (Home Premium, Ultimate, etc.) and use the product key to activate it. (Edit: you can also find the product key for the current installation of Windows using certain programs, such as Magical Jelly Bean Keyfinder.) See here for more on how to find and download a Windows 7 disk image, which you can then burn to a DVD. clpo13_(talk) 18:01, 23 January 2017 (UTC)[reply]

If you have a valid Windows 7 product key: https://www.microsoft.com/en-us/software-download/windows7

If you don't have a valid Windows 7 product key: https://www.ubuntu.com/download/desktop

--Guy Macon (talk) 18:08, 23 January 2017 (UTC)[reply]

Before you do ANY of the above, check if your computer has a recovery partition. A lot of laptops since xp / win7 days include a recovery partition which can reinstall the OS to the factory state. First thing I would try is try tapping "F" key used for "Recovery" immediate after turning the computer on. If this works, you're done. Just make sure you have any data you want to keep copied off the laptop. If it doesn't work, I can't find a good tutorial from HP it self but there's a few threads in the HP support forums which might be able to help. reset pavilion dv6 to factory state and recover from partition. Vespine (talk) 22:08, 23 January 2017 (UTC)[reply]

This may sound like overkill, but I'll post it anyway. You're going to sell a laptop to somebody you don't know. So you can't trust the next owner of the laptop. Therefore, you should securely wipe the hard drive. Simply deleting all files is not enough, but a tool like DBAN can do the job. At the same time, the next owner of the laptop can't trust you. After all, you're not a reputable computer salesman. You could have installed your own malware, unknown to the malware scanners. The logical result is that both you and the buyer should wipe the hard drive. You could deliver a Windows install dvd along with the laptop, but the new owner shouldn't trust that either. And maybe he doesn't want Windows at all; it only has 90% market share. PiusImpavidus (talk) 10:15, 24 January 2017 (UTC)[reply]

Note, some OEM PCs have a preinstalled key in BIOS/UEFI. Such machines, least Windows 10 does not ask to enter a key. --Hans Haase (有问题吗) 21:23, 26 January 2017 (UTC)[reply]

You can ask your local nerd to borrow his/her Windows CD for a couple of hours, or download and burn one yourself. (((The Quixotic Potato))) (talk) 14:45, 28 January 2017 (UTC)[reply]

January 24

Font descenders cut off

I have a font which has its descenders cut off in font viewer (Windows), Word etc.: [1] But the descenders are definitely there because in Inkscape they show up. And the font doesn't appear in Photoshop at all. ANy suggestions? Amisom (talk) 00:12, 24 January 2017 (UTC)[reply]

I've seen descenders cut off in Word before. In that case, the line spacing was manually set too small relative to the font and the font size. Maybe you can do this as an experiment -- increase the line spacing by a large amount and see if the descenders are still cut off. If they aren't, then line spacing is part of the problem. --100.34.204.4 (talk) 13:42, 24 January 2017 (UTC)[reply]

HP 6830s Windows 7 Corrupted, help!

Here's what happened. A user tried hibernating the machine (no idea why) and subsequently it got stuck in a boot loop where the machine wouldn't progress past the bios logo and the hit X to enter setup. I literally couldn't even hold down F8 before it would reboot and the loop would start again.

So I used the inbuilt system utilities to run a HDD diagnostic, and after 2 hours of that it checked out fine.

I grabbed hirens boot USB, loaded into that and changed the windows folder to windowsX. Rebooted, Lo and behold, the boot progressed this time to windows recovery. I let the recovery do its auto repair and I was back in windows.

Suprisingly, it wasn't smart enough to name windowsX to back to windows. It just created another windows folder with some rubbish in it.

So I went back into my boot USB. Changed it back manually to windows and rebooted. Unfortunately, windows is still confused and I get a boot menu now with two Windows 7 (recovered) options. One is from a previous install, which I don't use. Although it's hard to distingish which is which.

But anyway, when it boots I now get put on to a temporary profile. Any idea how I can get out of this mess, please?

Thanks. — Preceding unsigned comment added by 185.52.181.184 (talk) 00:15, 24 January 2017 (UTC)[reply]

I guess des SID of the user profile does not fit the machine's common part. Is suggest to backup all data and clean reininstall the machine. This will kill also malware. Aware to restore without propper and uptodate antivirus software. --Hans Haase (有问题吗) 21:20, 26 January 2017 (UTC)[reply]

Press the key combination Winkey + R. Type "Sysdm.cpl" (without quotes) in the box and press Enter. The System Properties dialog should open. Click the "Advanced" tab. Click the "Settings" button in the section named "Startup and Recovery". There you can chose the default operating system and the amount of time to display the list of operating systems. (((The Quixotic Potato))) (talk) 10:57, 28 January 2017 (UTC)[reply]

The Colorful Pins of the Asus Pi Clone

http://www.pcworld.com/article/3160097/computers/the-asus-tinker-board-is-a-powerful-raspberry-pi-rival-that-plays-4k-video.html

As can be seen in these pictures, the 40 GPIO pins of the Asus Tinker Board are color coded according to their own functions.

Sometimes, I use colored pins on my own boards to make it easier to locate +5V, GND and other pins. However, it's very time consuming to do this job. You have to insert colored pins one by one.

How do they mass-manufacture boards with colored pins? -- Toytoy (talk) 09:56, 24 January 2017 (UTC)[reply]

Looking at that photo, the whole insulator blocks aren't coloured. There's just a printed label that's been put across the insulator blocks (or maybe the colours are screenprinted directly onto the blocks). Coloured labelling for jumper headers is fairly common on motherboards (example), for both the case connectors (pwr/reset/driveLED etc.) and case usb connectors. -- Finlay McWalter··–·Talk 11:56, 24 January 2017 (UTC)[reply]

I think you're right. The colors are printed on the black plastic base. -- 180.217.167.66 (talk) 13:39, 24 January 2017 (UTC)[reply]

They don't look like they are printed to me, they look more like a piece of thin plastic tape that is pushed down over the pins. It looks to me like cut lines were probably put on the strip where the pins go rather than the pins just being pushed through to make the holes. Perhaps there is some machine on the web to do it if one can get the search terms right. Dmcq (talk) 18:28, 24 January 2017 (UTC)[reply]

→http://www.farnell.com/datasheets/2197507.pdf [2] --Hans Haase (有问题吗) 21:14, 26 January 2017 (UTC)[reply]

January 25

How safe are software repositories?

Can software repositories be a security risk? I have on mind CPAN or Pypi or similar? — Preceding unsigned comment added by 31.4.146.149 (talk) 23:29, 25 January 2017 (UTC)[reply]

Yes. They can be a security risk. Some form of security is necessary. First, you can use some form of public-private key encryption to ensure that the data you are receiving is coming from the repository itself and not a third party that has hijacked your connection. Second, you can use a key to decrypt a hash of the files and ensure that the hash of the file you received matches the hash reported by the repository. That just ensures that the file you received is actually from the repository. You have to trust that what is in the repository is supposed to be there. In the past, supposedly secret keys have been compromised, allowing someone to slip files into repositories. Depending on the repository, it could be hidden and you won't know about it. When it happened to Fedora, they widely publicized it and told everyone to change their repository keys and redownload packages. Finally, you have to trust the repository. Do you really trust "Joe Bob's Super-Cool Repository for People Who Don't Care About Computer Security"? Do you trust a repo that is more focused on pushing out every daily change to every package at the expense of checking security? It is purely up to you. I use Redhat's repository, which I trust more than other repositories. I used to use Adobe's repository, which I didn't really trust at all because I simply don't trust Adobe. It was an accepted security risk for me. All in all, security risk of your chosen repository is something to keep in mind, but it isn't as important as social engineering, phishing, baiting, etc... 209.149.113.5 (talk) 16:14, 26 January 2017 (UTC)[reply]

All true. That being said, I generally trust CRAN, CTAN, and other large/famous/old code repositories - they do their own due diligence to keep malicious code out of their servers, and they have many, many users who will quickly report any problems. I have not personally heard of anyone having any problem with materials downloaded from these fairly reliable sources. I have not personally used CPAN, but I'd probably extend them a basic level of trust as I do for CRAN and CTAN, neither of which are remotely like your your hypothetical "Joe's super cool" example, in terms of security nor frequency of changes being pushed. SemanticMantis (talk) 16:28, 26 January 2017 (UTC)[reply]

January 26

Firefox vs large images

Yesterday in a heroic feat my Firefox 50.1.0 managed to load and open a 10,380 × 6,719 px image. Sometimes, however, it fails to load even smaller images, today for instance it loaded a 7,360×4,912 px-image only after a second try. Can't figure out why this happens, seemingly cache purging doesn't help and probably internet connection isn't implicated (running on Win 7, 2 GB RAM). Brandmeister^talk 12:54, 26 January 2017 (UTC)[reply]

That isn't much RAM by today's standards, you might try an upgrade (or a new computer). That's my only guess. I'm having no problems with Win10 / Firefox 50.1.0 / 8 GB. When I want to examine the pupils of Donald Trump's eyes, I view File:Donald Trump official portrait.jpg at full size (4,032 × 5,040). No problem viewing your larger example, although it took 6 or 8 seconds to download (wi-fi). ―Mandruss ☎ 13:16, 26 January 2017 (UTC)[reply]

I've only 1 GB RAM on the machine I'm currently using, and I get a message that your 10,380 × 6,719 px image cannot be displayed because "it contains errors". The next size down displays perfectly. I always blame intermittent internet problems. I've no trouble with the Donald Trump portrait, though it takes a while to load. Dbfirs 13:49, 26 January 2017 (UTC)[reply]

Flush browser caches STRG+SHIFT+DEL in browser. Else use CCleaner. --Hans Haase (有问题吗) 21:07, 26 January 2017 (UTC)[reply]

No need, it's working now in just 1 GB of RAM (and still running several other applications), so the problem must have been with the internet connection. I wonder why Brandmeister thinks his internet is not implicated. Dbfirs 21:21, 26 January 2017 (UTC)[reply]

Thanks, I was not sure whether it's internet. Brandmeister^talk 20:16, 27 January 2017 (UTC)[reply]

January 27

Chromebook keyboard shortcuts for switching tabs

How do you switch tabs on a Chromebook?

I work on a Chromebook and I need to know how to switch tabs quickly. Please help.71.6.6.210 (talk) 19:21, 27 January 2017 (UTC)[reply]

Does pressing "Ctrl-Tab" work for you? 209.149.113.5 (talk) 19:26, 27 January 2017 (UTC)[reply]

Yes, but it only moves me one tab to the right. How do I move to the left?71.6.6.210 (talk) 19:30, 27 January 2017 (UTC)[reply]

"Shift-Ctrl-Tab"? Rojomoke (talk) 20:22, 27 January 2017 (UTC)[reply]

That works. Thank you. That is the only keyboard shortcut I don't know. 71.6.6.210 (talk) 20:30, 27 January 2017 (UTC)[reply]

File extension

Hello there,

My environment here is HP Pavilion, Windows 10, MS Blend For Visual Studio. I have this C# code located in github that I need to copy into the Blend to make a functional project. I began with creating folders in Visual Studio 2015/Projects and naming them appropriately. In the last two folders I created files I need. Then I renamed the files with the names I need with .cs extension. Unbeknownst to me the Windows kept .txt extension attached to .cs and .sln extensions. So now my files look like this ****.cs.txt and the Blend cannot find them. I tried to rename them via cmd prompt but when I came to the final folders cmd could not find them. They turn out to be hidden. When I use numerous GUI/windows in File Explorer, those .txt extension aren't visible.

It is all very bizarre. The only way I see is creating a blank or WPF projects in the Blend and loading the files with the code. This is a tedious job. I have already done it once copying github files to my project folder that does not work. Any suggestions.

Thanks, - Alex

This sounds like "Hide extensions for known file types". The fix is virtually the same for any version of Windows. -- zzuuzz ^(talk) 22:22, 27 January 2017 (UTC)[reply]

January 28

PCBSD wired dhcp not working. What can be the problem?

I have an pc that has the windows os and pcbsd installed at it.
The modem i use is Technicolor TD5130V2, the pc is connedted to it by wire that is then to the internet.
I can use the internet as usual when working with windows, but when I try to use pcbsd, the dhcp doesnt work and it gets no ip, if I try to put fixed ip, it also doenst work, it doenst save the values. I have some usb wireless network adapter, and I tried and it works with pcbsd and its the only way right now I am able to use network/internet with pcbsd.
What can be the problem?201.79.78.226 (talk) 01:10, 28 January 2017 (UTC)[reply]

It may be that the onboard ethernet network adaptor of your system is not supported by the kernel you are using. The dmesg and ifconfig -a shell commands may be useful to gather more information. If you are having difficulty finding proper user discussion resources and help for PCBSD, remember that it is based on FreeBSD, so its resources (i.e. documentation, user mailing lists, IRC channels) may be helpful as well. 76.10.128.192 (talk) 00:04, 29 January 2017 (UTC)[reply]

Home Network vs. Internet

I've been playing around with a small home web server that I access through my router: the IP address is in the 192.168.1 range that is reserved for personal networks. I know that if I go to my parent's house and type in the address, it won't connect, but how far does my home network extend? Would someone have to connect to my router in order to access my server? And if I purchased a domain name, does the IP address come with it? That is, if I bought a domain name, can I point it to my server and access it from across town (not that I'd do this--it's probably a bad idea--but I'm trying to better understand the difference between a local server, and a server that is a part of the Internet). OldTimeNESter (talk) 01:16, 28 January 2017 (UTC)[reply]

Hi User:OldTimeNESter! 10.0.0.0 - 10.255.255.255 and 192.168.0.0 - 192.168.255.255 are so-called private address ranges, they can only be used inside your Local Area Network (e.g. 192.168.1.2 can communicate with 192.168.1.3 over the LAN). So currently the only devices who can connect to your web server are those connected to your local area network, which probably consists of a router and a handful of devices inside your home.

You also have a public IP address which may be used for communication between devices on the internet (outside of your LAN), for example 172.217.17.142. If you want to access your server from somewhere else (outside of your LAN) then you won't need a domain name but you'll need to tell the router that all connections to your public IP address 172.217.17.142 on the port 80 (which is commonly used for web servers) should end up at 192.168.1.2 (or whatever the local IP address of your web server is).

When you've done that then you can access your web server from almost anywhere by typing in the IP address. But humans are kinda bad at remembering IP addresses. That is why we invented domain names. There are computers, we call them DNS servers, who know which domain name(s) belongs to which external IP address. For a small fee you can register something like www.oldtimenester.com. If someone tries to access that website (and everything is configured correctly) then a DNS server will say "if you want to reach www.oldtimenester.com then you will need to go to 172.217.17.142". The router is responsible for the next step, it knows that connections to 172.217.17.142 on port 80 should go to a device on your local network, in this example 192.168.1.2. (((The Quixotic Potato))) (talk) 06:08, 28 January 2017 (UTC)[reply]

I'd note you can't be certain this will work no matter what you do. While CGNAT is relatively uncommon in the developed world for home user connections, it does exist. Similarly some ISPs may block port 80 or do other weird things which prevent it. IPv6 may help but even if it's supported which remains a big if, there's still a chance your ISP will have done something which prevents it.

Assuming the IP isn't directly allocated do your computer, you'd also actually need to be able to enable portforwarding on the router, or replace the router, but these two aren't always possible. (Port forwarding was mentioned above, but not that it may be simply not possible.) Also if your IP isn't static, particularly if it changes frequently, you'd want to set up some sort of automated dynamic DNS for your domain name.

Considering a webserver is probably a bigger and more vunerable target, a better solution may be to use some sort of good VPN solution or maybe SSH, so the parents home computer can be on your local network. (Not that this will completely eliminate the above problems.)

Nil Einne (talk) 16:26, 28 January 2017 (UTC)[reply]

Thanks to both of you for your help. I knew that my ISP assigned my router an Internet address, but I never thought that it could be used to access my local network from outside of it (subject to the caveats listed above). I know they don't assign me a static IP, but I typically get the same one every time I connect; I don't know whether they block port 80, or do anything else to stop this sort of thing, but since I have a standard subscription (i.e. I really shouldn't be running a web server over it), it wouldn't surprise me. Like I said, though, this is just a thought experiment to help me better understand how my LAN relates to the Internet at large. OldTimeNESter (talk) 16:50, 28 January 2017 (UTC)[reply]

Accessing internet via wifi

My mom has an old PC (Windows 2000, I think) with no current internet access. Her community does have free wifi, though. So, what would I need to get her to access the internet ? StuRat (talk) 17:14, 28 January 2017 (UTC)[reply]

You can probably get a PC for free that is better than the one she currently has. If the computer has USB ports then I would recommend typing "USB WIFI" in your favorite search engine (if it does not then it is probably so old that it is probably unusable, realistically speaking). The devices are commonly called "USB wifi adapter" or "USB wifi dongle" and cost less than 10 dollar. A computer that old probably won't be able to run modern antivirus though! (((The Quixotic Potato))) (talk) 17:26, 28 January 2017 (UTC)[reply]

@StuRat: I wouldn't be surprised if you can get an old phone for free that is better than the PC she currently has! If you are willing to invest some time and/or the amount of money that it costs to get a six-pack of beer then I would recommend trying to get a PC or phone that is more up-to-date. (((The Quixotic Potato))) (talk) 17:29, 28 January 2017 (UTC)[reply]

Honestly, the cheapest and simplest option would probably be a new laptop or a wifi-enabled tablet computer. Amazon lists Chromebooks and other cheap laptops for under US$200 right now. I don't think it's economically feasible to harden an ancient PC to be safe to use on the current internet, even if you manage to find a wifi card and drivers. Unless you want your mom to handle OpenBSD, of course ;-). --Stephan Schulz (talk) 17:33, 28 January 2017 (UTC)[reply]

If you want to spend less then I recommend offering a six-pack (or even a case) of beer for some second hand hardware; that is what I do if I cannot find the thing I want for free. Making an ancient PC usable is do-able, but it takes time, and it is probably quicker and easier to get newer hardware. (((The Quixotic Potato))) (talk) 17:45, 28 January 2017 (UTC)[reply]

You have to understand that she is 82 and unable to adapt to change. I had to replace her monitor and she still complains that it's just not the same, although I can't see any difference. The extent of her internet access would likely be to access the daily weather on a favorite/bookmark I would set up for her. I'd also like to have internet access there, say to look up an address for her, when I visit. StuRat (talk) 18:35, 28 January 2017 (UTC)[reply]

Well, it is very likely that the computer has a USB port if it is running Windows 2000 so in that case I would recommend buying an old "USB wifi adapter" or "USB wifi dongle" for less than 10 dollars (make sure it supports your Windows version, many of them support XP and up). Ideally it would have the drivers required on a CD. I don't know where you live, otherwise I would post a link. (((The Quixotic Potato))) (talk) 18:50, 28 January 2017 (UTC)[reply]

You should post the actual specification of the computer if you want better answers. I also think it is a bit strange that Win2k is used on a home PC – win2k lacked a home version and was mostly used in the professional environment. Ruslik_Zero 18:58, 28 January 2017 (UTC)[reply]

Maybe it's 98, then. I'll post specs next time I get over there. All she does is play solitaire on it now. StuRat (talk) 19:49, 28 January 2017 (UTC)[reply]

Think it might be better to view your mother as someone that finds it frustrating that takes her 'longer now' to adapt and would rather things no longer changed. However, over her lifetime she would have seen and lived through many changes. Put it to her, that just as women no longer wear uncomfortable restrictive wale-bone corsets, no women to day needs restrictive, uncomfortable Windows 2000. Then put in some quality-time to hold her hand until she becomes familiar with (say) a Chrome-book. Hands on experience with someone there (you) to avoid the frustration that comes about from the unfamiliar will dissolve the unable to adapt bit. Remember too, when you show her anything, perform your key-stokes very, very slowly. So that she has time to understand what you are showing her. Also, pause a lot, to give her time to ask questions. This is because as one grows older one's BS detector no longer automatically accepts what is said unless the explanation makes sense to what has been said before. The financial aspect of a new computer is a pittance really when one comes to think about it. What you receive back from the interaction though, could be beyond price. If she only uses it for solitaire, introduce her to Google. She must have some interests that google will reopen.--Aspro (talk) 20:20, 28 January 2017 (UTC)[reply]

Against what background you calculate the entropy of a word?

Against what set do we calculate the entropy (as Entropy (information theory)) of the words in a real text?

If it begins with "The", for example, would you consider it's one among thousand of words?

If a reader knows that many texts begin with "the" would that mean that for him (but not for others), this word has a lower entropy?

If a reader has a really limited vocabulary (1,000-2,000 words), would that means that the word has a lower entropy too? It would be just one among 1,000-2,000.--Llaanngg (talk) 19:52, 28 January 2017 (UTC)[reply]