Wikipedia:Reference desk/Archives/Computing/2010 March 17

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March 17[edit]


How do u get your friends back on page when it has been wiped out for some reason and what is a number to call for assistance? —Preceding unsigned comment added by (talk) 00:41, 17 March 2010 (UTC)

Gonna need more details than that, what exactly are you talking about?--Jac16888Talk 00:45, 17 March 2010 (UTC)

You might know what you're on about, but we have no idea unless you provide more details....Chevymontecarlo. 15:43, 17 March 2010 (UTC)

home network - slow speed for 1Gb[edit]

My new 1Gb home network is performing at only about 20%.

In my home network I replaced a 10/100 wired router with a 1Gb wired/802.11n wireless router. Before I made the change I timed the transfer of a 338MB file. It took about 37 seconds. One computer already had a 1Gb Ethernet card, with a cheap cat-6 cable. I put a 1Gb Ethernet card in another computer. (It still had a cat-5 cable.) I tested the transfer several times and it took 17 to 22 seconds - about twice as before but about 5 times slower than I thought it should be. I replaced the cat 5 cable with a cat 5e cable - no noticeable difference in speed.

I replaced the cat 5e with a high-quality cat-6 cable and restarted the router. (The other computer has the cheap cat-6 cable.) Now the transfer took less than 5 seconds - the speed I was expecting. (Note: I did this test only one time so it is possible I copied the wrong file.)

Now, about 12 hours later I tested again and it is back to 17-22 seconds. I restarted the router - same speed.

The router shows that both computers are connected at 1Gb. The Netgear utility shows both connected at 1Gb. The Netgear utility also shows the transfer performance at 18-19%, which agrees with what I measured.

Why am I getting only about 20% performance? Could the problem be the cheap cat-6 cable? Bubba73 (You talkin' to me?), 05:13, 17 March 2010 (UTC)

It's possible that the network isn't your bottleneck; a nearly-full, highly-fragmented, or just poorly-performing hard drive could easily only be able to manage 20MB/second sustained write speeds. —Korath (Talk) 07:29, 17 March 2010 (UTC)
Though, having reread what you wrote, it's more likely that it's on the sending end—338MB will probably fit into ram cache, so the slow first send indicates a slow read from the hard drive, and the repeated test is sending it from your source machine's read cache. If this is the problem, then you can expect the first test to be slow, and a subsequent repeat test to be limited only by your network, even if you don't reboot your router in between. You probably want to be benchmarking with larger files, certainly ones larger than the amount of ram you have in either machine. —Korath (Talk) 07:42, 17 March 2010 (UTC)
Repeated tests are not significantly faster. Bubba73 (You talkin' to me?), 15:18, 17 March 2010 (UTC)
My first suggestion is to make sure jumbo frames are enabled on both computers, assuming that the Netgear router supports jumbo frames. There is often a jumbo frames setting in the device driver settings for the ethernet interface, which you can get to through Device Manager. But it's unrealistic to expect to get anything close to 1 Gbps of actual throughput on most gigabit hardware, especially if hard drives are involved; see this Coding Horror blog entry for example, or this more recent Tom's Hardware article. -- Coneslayer (talk) 11:28, 17 March 2010 (UTC)
I don't think it is entirely the hard drives. One computer has two SATA drives and the other has two ATA drives. On the one with two SATA, I can copy the file to the same drive or to the other in a couple of seconds. On the one with two ATA drives it takes under 10 seconds to copy to the same drive or to the other drive. But it is somewhat faster copying from the ATA to the SATA than the other way around. The SATA to ATA gives about 18-19% network performance and ATA to SATA gives about 25% network performance. But still the network performance is about half of the HD to HD performance on the old ATA drive-to-drive. Bubba73 (You talkin' to me?), 15:16, 17 March 2010 (UTC)
Both cards had jumbo cache disabled so I enabled it. No improvement. I rebooted both computers and the modem. I also disabled Firewire (because I don't use it), and now it is up to about 24% from 18-19%. Bubba73 (You talkin' to me?), 15:47, 17 March 2010 (UTC)
Tom's Hardware article was extremely informative. The HD must be the bottleck. He said to expect 20-65MB/sec, and I'm getting approximately the low end of that range. One of the machines is old with the old ATA drives, so that seems to be what I can expect. My thanks to everyone.

Bubba73 (You talkin' to me?), 16:04, 17 March 2010 (UTC)

"Ticking" HDD[edit]

I recently bought an external drive (1.5TB, Seagate) and it sporadically makes loud ticking noises when turned on. Usually when first turned on it will do it for about 30 seconds, during use it will start ticking maybe once every 15 minutes, giving it a large read/write job seems to stop it temporarily.

It's the same sound I've heard from drives with "crashed heads" (not sure if thats the correct term) so it's giving me some angst ... is it defective? I assume it's the heads banging into the case or something thats making the noise, that can't be good for it. Will it die completely soon? I'm loath to send it back since it has more than 1TB of data on it so I'd need to buy a new drive to put all the stuff on while I sent this one away to get replaced/fixed but obviously I have to, just hoping for a second opinion or an alternative. Thanks Benjamint 07:58, 17 March 2010 (UTC)

Ticking is indeed very often a sign of drive failure. It would be a good idea to run a badblocks test and some S.M.A.R.T. self-tests. If either of those return any errors, it's best to replace the drive ASAP, as any further use will likely aggravate the problem. If all the tests come up clean, the drive might still be good - but if you keep it, be sure to periodically repeat those tests. --Link (tcm) 11:22, 17 March 2010 (UTC)
Sounds suspiciously like the Click of death. You should immediately back up all important information--I wouldn't trust a hard drive that is making that sound. --Zerozal (talk) 17:20, 17 March 2010 (UTC)
Ticking is bad. Backup now. Shadowjams (talk) 21:11, 17 March 2010 (UTC)
Is it only damaging itself or at risk of dying when it is actually ticking? With about 1.2TB of data to copy over it would need to be running for several hours... should I do it incrementally in order to not tax it too much? Or since it doesn't seem to tick when it's reading/writing is it actually functioning normally during the backup processs? Benjamint 21:18, 17 March 2010 (UTC)
It's hard to know what exactly the "ticking" sounds like. It's conceivable that it's just a loud platter, but most rhythmic sounds from a HD, especially a modern one (which are usually quiet), is cause for concern. I think it would be prudent to backup in that instance. It's possible that reading sections could damage them, but that data's in jeopardy anyway. You have to use your own judgment, but in my experience, new drive sounds always precede a crash; I would prioritize the most important data first for backup and hope for the best. Shadowjams (talk) 03:27, 18 March 2010 (UTC)
My drive has been "ticking" (1 tick every few minutes when it is idle) for 3 years, and it's fine. -- (talk) 08:52, 18 March 2010 (UTC)
This type of ticking could be the disk powering down after a certain time. Maybe a background process wakes it every minute or so. If you listen very carefully you might be able to hear if there is less motor noise before or after the click, though drives are usually much quieter than cooling fans so you might not be able to tell. -- Q Chris (talk) 10:00, 18 March 2010 (UTC)
I had exactly the same experience and concerns. Seagate's forums have a lot of posts about it and a general web search produces a lot of results as well. Seagate recommends you maintain an up–to–date backup, (regardless of whether the drive itself is intended to be a backup). I purchased a backup Western Digital product that runs much more quietly.—Machine Elf 1735 (talk) 17:28, 19 March 2010 (UTC)

Keys suddenly not working[edit]

a e h l m r and w. What should I do please? - Kittybrewster 10:43, 17 March 2010 (UTC)

Turn off. Unplug the keyboard. Turn it upside down and shake out the gook. Replug the keyboard. Try again. If that fails, get a new keyboard. (Did anything else happen? No accidents with liquid, for instance?) --Tagishsimon (talk) 12:46, 17 March 2010 (UTC)
Step 1 and 2 are optional. Step 4 is fairly cheap nowadays.--Stephan Schulz (talk) 12:57, 17 March 2010 (UTC)
You could try prying off the key tops with a flat-head screwdriver (or similar tool) and clean under there. You can also get cannisters of compressed gas for cleaning a keyboard, but it's probably as cheap to buy a new keyboard. Note that this advice and the previous applies to a desktop PC with a separate keyboard; you don't say what sort of keyboard it is.--Normansmithy (talk) 17:01, 17 March 2010 (UTC)
(Laptop). Success! Oh joy. Thank you. - Kittybrewster 17:30, 17 March 2010 (UTC)
Just curious...which action fixed it ? StuRat (talk) 23:10, 17 March 2010 (UTC)
Handed it to girlfriend who cleaned it. - Kittybrewster 09:16, 18 March 2010 (UTC)
That method is more likely to result in her breaking it over you head, which is one way to fix a problem keyboard. :-) StuRat (talk) 03:36, 20 March 2010 (UTC)
Using the "turn it upside down and shake vigorously" method ? StuRat (talk) 15:33, 18 March 2010 (UTC)
Regarding buying new keyboards - I actually clean my keyboards even if a new (used but still) unit will cost me less than a kebab, because this just generates less electronic waste. Take apart. Wash all non-electronic components with dishwashing liquid. Put back together. --Ouro (blah blah) 07:46, 19 March 2010 (UTC)

Greasemonkey Question[edit]

Is it possible for a greasemonkey script to make the browser load a url? How would you do this? Thanks --Fire2010 (talk) 15:35, 17 March 2010 (UTC)

That is an example of cross-site scripting, and because it represents an inherent security risk, GreaseMonkey has limitations about what you can do with it. See this forum post and this documentation for GM_xmlhttpRequest. (Compare with the standard JavaScript XMLHttpRequest. For more information about this issue, see the Same Origin Policy from Mozilla's developer website. Nimur (talk) 15:56, 17 March 2010 (UTC)
I gave this query a suitable title. --Sean 18:00, 17 March 2010 (UTC)

Windows networking / Samba and subnets[edit]

I'm trying to understand the interaction between windows/samba file-sharing/workgroups and the local subnet. Specifically my question is, can I share files on a LAN, with a basic windows setup (no master domain controllers or anything advanced) between machines on different subnets? Is it that they don't see each other because they simply don't receive the broadcast messages?

Obviously these packets don't get routed by most ISPs, but is that because ISPs block them or because a NATed network will have a different subnet (and in which case, if a client wasn't NATed, would they be able to share with that non-private subnet?). I'm not so much looking for a specific answer so much as I'm trying to understand how these two interact, so any push in the right direction would help. Shadowjams (talk) 19:01, 17 March 2010 (UTC)

To the first part of your question: yes, that's right. In that scenario, if you type \\ (or whatever; the ip address of the other machine) in your Explorer location bar, you should still be able to reach it directly. It's just that Windows discovers nearby hosts by using NetBIOS name resolution, which broadcasts on the local subnet. If your DHCP server also incorporates a DNS server, or if you manually add the hostname/ip pairs to your Hosts file, you should be able to access it by name, although I don't think Windows will be able to discover them automatically.
To the second part, there's a couple issues. As I mentioned, netbios name broadcasts are local subnet broadcasts, so they won't make it onto the internet. And yeah, a lot of ISPs might block SMB traffic. The main reason there isn't to block file sharing, but because there are a lot of viruses and worms that target the SMB and netbios ports, since they're open on a lot of Windows machines by default. But if you weren't NATed, and your ISP didn't block it, then you should be able to do \\ or whatever, and be able to reach it. Indeterminate (talk) 03:36, 18 March 2010 (UTC)
Very helpful. Thanks. Shadowjams (talk) 03:57, 18 March 2010 (UTC)

One DVD won't play in laptop[edit]

Hi. I'm running a Windows 7 Dell laptop. I recently bought a new DVD boxset, and it won't work in the laptop: I put any of them in, the noises cycle round and round and round, but it won't show up or function. Other DVDs work perfectly, and the "defective" DVD is perfect in a desktop PC and in a DVD-player. Any ideas on what's up? ╟─TreasuryTagassemblyman─╢ 19:18, 17 March 2010 (UTC)

Pardon me, have just clarified: of the six DVDs, numbers 1, 4 and 6 are subject to the problem listed above; the others work perfectly... :O ╟─TreasuryTagCounsellor of State─╢ 19:27, 17 March 2010 (UTC)
You didn't state the title. A web search might reveal others with the same issues— bad batches have occured. ---— Gadget850 (Ed) talk 19:55, 17 March 2010 (UTC)
No, tried that – no such luck. Since it works on seemingly every other device, however, I'm not sure it's going to be the DVD's "fault"... ╟─TreasuryTagbelonger─╢ 20:09, 17 March 2010 (UTC)

If you're using some horrible DVD playing software that Dell preinstalled, or Windows Media Player, all bets are off. Try with VLC or SMPlayer, or try making an image first with dd or ddrescue. ¦ Reisio (talk) 22:22, 17 March 2010 (UTC)

If the disk doesn't even show up in My Computer, you won't be able to make an image, and other media players won't help either. If the disk really doesn't show up in My Computer at all, it sounds like you might have a defective DVD drive, which you should talk to Dell Support about. Indeterminate (talk) 00:12, 18 March 2010 (UTC)

Google Earth[edit]

It may be my own ignorance - probably the case as usual - but whenever I use the latest version of Google Earth and narrow down to the desired location - and then click on the chosen "bubble", everything works fine. The bubble rotates and points me up or down the desired street or whatever, and then offers me a chain of cameras. I soon discovered that if I try to leapfrog to a distant camera further away than the closest in view, the system will crash and I will get an error message and have to start over. So I now don't do that; instead, I religiously move from the closest camera to the next furthest and so on - but I still invariably crash the system and get a message that says, "Google has discovered a system error" or suchlike. Is it me or is it something else I am unaware of? I really would like to know as I really enjoy using Google Earth but the interruptions are spoiling it for me. Thanks folks. (talk) 20:00, 17 March 2010 (UTC)

Well, it sounds like you've found a bug. It could be due to:
  • a bad install of the program - you could try to fix this by uninstalling and reinstall Google Earth,
  • some configuration problem on your computer, maybe a driver or a library or something. If this is the issue, you might have to reinstall your OS to fix it.
  • a bug in Google Earth - if you try this same thing on another computer, and it does the same thing, this is probably the issue.
If it turns out to be the last one, you can report a bug and hopefully Google will fix it in a future release. Indeterminate (talk) 00:09, 18 March 2010 (UTC)

.exe to .dmg[edit]

How can I convert a .exe file for windows to being accesible on an Apple Macintosh? Do I need to convert to .dmg? What program can I use to do so? —Preceding unsigned comment added by (talk) 20:14, 17 March 2010 (UTC)

Could you explain what exactly you want to do with the .exe file when you say "accessible"? If you want to run a Windows executable file (like HalfLife.exe, for example), it won't work, because the .exe file format is specifically designed to run under a DOS or Windows operating system. Comet Tuttle (talk) 20:18, 17 March 2010 (UTC)
That's too strong. There are various emulators for running Windows executables on things other than Windows. See VMware Fusion and Parallels Desktop for some MacOS ones. --Sean 20:41, 17 March 2010 (UTC)
Also, if you tell us what program you are interested in someone may know of a Mac port. (talk) 21:06, 17 March 2010 (UTC)
.EXE files are generally compiled to work only on Windows machines. There is no one-step solution to running them on a Mac—they are compiled for a different operating system. They cannot be just easily converted into one another. The two major ways for running Windows programs on Macs are either
  1. through a virtual machine (e.g. VMware Fusion, Parallels Desktop, VirtualBox), in which you basically run Windows itself as a program in the Macintosh, and the EXE in that virtual instance of Windows (advantage: pretty easy to set up, if you have an extra copy of Windows; disadvantage: you're running two operating systems at once and that is much slower than just running one of them),
  2. through a dual-boot system (BootCamp), whereby you run Windows itself on your Mac hardware (advantage: quicker than virtualization because you're running Windows and only Windows; disadvantage: a bit harder to set up, opens your main computer up to all of the "dangers" of Windows, computer needs to be rebooted every time you want to switch between operating systems).
  3. there is also Wine, which manages to somehow run Windows applications more natively in a Mac OS, but the few times I tried to get it to work, it seemed rather impossible even if you were pretty well experienced with the Unix aspects of Mac OS X. (Maybe it has gotten easier. But if you're asking whether EXEs can be converted to DMGs, you are probably not better in this respect than I was.)
And of course the other option altogether is to try and find a version of the program that has been compiled specifically to run on a Mac, which may or may not be possible depending on the program. --Mr.98 (talk) 21:31, 17 March 2010 (UTC)
All correct except part of your first point. Modern virtualization solutions like e.g. the free VirtualBox are running the virtualized OS at very nearly native speed. You will only lose significant performance if you are short on memory, if the host OS is running additional resource-intensive tasks, or if you rely on some hardware that is not supported by the virtualization. I'm e.g. running Ubuntu with VirtualBox on MacOS-X, and its indistinguishable from a native install. --Stephan Schulz (talk) 12:34, 18 March 2010 (UTC)
Put simply - there is literally no way to turn a Windows EXE into a Mac DMG - that's really impossible for all sorts of technical reasons. What you have to do is to find a way to persuade the Mac to behave sufficiently like a Windows machine that it'll run the EXE "as is" - and previous posters have explained that very well. SteveBaker (talk) 09:10, 19 March 2010 (UTC)
Well, if we want to be finicky, its quite trivial to turn a Windows EXE into a DMG. DMG is just a disk image and does not care whats inside. Of course, turning an EXE into a DMG that contains an installer that will install the EXE as a runnable program is something very different and, if not impossible, not possible with plausible effort. --Stephan Schulz (talk) 13:44, 19 March 2010 (UTC)

Win 7 - opensource and/or free video editing software?[edit]

First, thank you to everyone who posted answers to my question a week back about bulletproofing my mother-in-law's new Win7 PC. That went very well! As a follow-up, I'd like to know if anyone has a particular opensource and/or free video editing software they can recommend for Windows 7? My dear M-i-L has dreadfully boring charming digital videos of her 2 cats that she'd like to edit... (talk) 22:14, 17 March 2010 (UTC)

The best place to start are our articles on video editing software, List of video editing software, Comparison of video editing software. Nimur (talk) 22:23, 17 March 2010 (UTC)
Windows Movie Maker? ¦ Reisio (talk) 22:24, 17 March 2010 (UTC)
These days, most video cameras come with some basic video software on a CD. Depending on the model, that will simply let you copy the video off the camera, or also provide some editing capability. Alternativly, the camera manufacturer might have something you can download from their official site. As mentioned above, Windows has a basic tool installed by default and there are others available. In my experience, using the software provided with the camera and Windows Movie Maker has proved acceptable for my purposes. Astronaut (talk) 23:06, 17 March 2010 (UTC)
As the Windows Movie Maker says, Windows Movie Maker has been replaced by Windows Live Movie Maker in Windows 7. -- (talk) 08:51, 18 March 2010 (UTC)

avidemux --F08VUHOnP9hbuBu9EfJz8Q (talk) 23:12, 22 March 2010 (UTC)