Wikipedia:Reference desk/Archives/Computing/2009 June 24

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June 24

Download Microsoft Security Essentials?

Resolved

Anyone knows a direct link for Microsoft Security Essentials? My MS Connect account just gives me a strange error "ID error", and I can't download it... :(

Here is the official site. Since your IP address is not in one of the areas covered by the beta, though, you probably won't be able to download it (unless you use a proxy, of course). Algebraist 00:21, 24 June 2009 (UTC)

It's just a cut-down (but Windows 7 compatible) version of OneCare, without the firewall, and I understand they only have 75,000 copies available for the beta, for US, Israeli and Brazilian customers.- KoolerStill (talk) 01:20, 24 June 2009 (UTC)

Well, you could always head over to Softpedia. I'm currently testing out the beta under the Windows 7 Release Candidate. Note that the installer will require that your copy of Windows be genuine (Not to imply that it isn't). A restart will also be required. The install shouldn't take too long though and the program is pretty simple to both use and configure. I can't really offer an opinion on how effective the product is against malware is at the moment though. I would not suggest using it as your primary anti-virus at this time (It's still a beta and its effectiveness unproven) unless it's a test machine.--Xp54321 ^{(Hello! • Contribs)} 04:10, 24 June 2009 (UTC)

I ended up finding it!. But thanks! the softpedia link is probably safer. Greetings!

Here's a video review of Microsoft Security Essentials if anyone's interested. :-)--Xp54321 ^{(Hello! • Contribs)} 01:43, 25 June 2009 (UTC)

What does ActivePython give over and above pywin32?

It is clear that ActivePython includes pywin32. What extra functionality does ActivePython give? -- Q Chris (talk) 07:34, 24 June 2009 (UTC)

Just from glancing at it, it looks like it's a distribution, meaning that they've packaged the pywin32 extensions up with a Python interpreter to be more user-friendly and easier to install, as well as offering end-user support. Their website says they also offer additional documentation. Basically, ActivePython seems to be the kind of thing an ordinary user or company would install, while pywin32 seems targeted at Python developers. Is that what you were asking? Indeterminate (talk) 00:14, 25 June 2009 (UTC)

Using fields in finalizers

Is it safe to use class fields in finalizers? I've heard somewhere that some fields may be nulled out or collected during a finalizer... --wj32 ^t/c 11:47, 24 June 2009 (UTC)

I'm going to presume you're talking about Java. It's always safe to refer to any field you can refer to; the whole job of the garbage collector is to destroy all and only those things to which it is impossible to refer (and thus impossible to care about). The weird things about finalizers are that they can be invoked with an arbitrary delay (if the system even bothers to run them at all) after the object becomes unreachable, and that they make the object reachable again! The garbage collector knows where everything is, of course, but it's not usually counted as a source of reachability because it never does anything with the unreachable objects it sees except destroy them. But when it invokes the finalizer, a reference to the "doomed" object gets pushed back across the veil and shows up on the stack of some thread again. (The stack (and certain special pointers like to the Thread object itself) of each thread and the collection of static fields (of classes loaded by the bootstrap class loader) are the roots of the reachability graph.) So an object being finalized can "rescue itself" (and thus any objects reachable through it) by posting some reference to itself into some other, reachable field (by mutating an object that another thread can already reach, or adding a reference to itself to some static field). Even if an object fails to do so during its finalizer, there may yet be run a finalizer of some other object through which it is reachable, and that object might rescue itself or just the first object. Finally, even if an object is rescued when or after its finalizer is called, the garbage collector will never call it again; once it becomes unreachable a second time, the garbage collector will simply destroy it. (Of course, if some other object that has a reference to the twice-doomed object (and which thus — think about this — must be unreachable itself) has not had its finalizer run, the twice-doomed object can't be destroyed until that finalizer is run, and so it may get rescued again.)

So there are really two levels of "unreachable" (in addition to the "weak reachability" and so forth): an object that is unreachable from the usual sources but is reachable from some object (possibly itself) that has a finalizer that has never been run is only "mostly dead" because it can't be destroyed until all such finalizers are run, and because any of them may rescue it. Any object that is reachable neither from the usual sources nor from any object that has a finalizer that has never been run is truly gone: aside from examining memory usage, there is no way to tell whether the object still exists or has already been collected. (PhantomReferences complicate this: if a phantom reference exists to an object, it prevents it from being actually collected but does nothing else — creating a third kind of "unreachable". It may still have its finalizer run, and (I believe) its fields cannot prevent other objects from being collected. I imagine that the implementation could even go ahead and collect the object; how would you know?) --Tardis (talk) 15:45, 24 June 2009 (UTC)

Using other people's image

I noticed on blogger.com you can add the URL of an image instead of uploading it yourself. Does this avoid copyright? I am not asking for legal advice...--217.227.73.165 (talk) 14:20, 24 June 2009 (UTC)

In many legal cases around the world, linking to something on the web is equivalent to making it available on your own website. In many other legal cases around the world, linking to something on the web is not equivalent to making it available on your own website. So, the answer is: It depends on where you are and how good your lawyer may be when you go to court. -- kainaw™ 14:38, 24 June 2009 (UTC)

I don't really plan on going to court. The countries that interest me most really are: US, UK, Netherlands & Germany if anybody has any info. Thanks Mr Kainaw! :))) --217.227.73.165 (talk) 14:43, 24 June 2009 (UTC)

The relevent term is Inline linking (but see also Deep linking) - the article only briefly mentions one case in the USA - Perfect 10, Inc. v. Amazon.com, Inc. - personally I would recommend against it if you want to totally avoid those court cases - it's clearly a bit cheeky...83.100.250.79 (talk) 15:27, 24 June 2009 (UTC)

You're basically using someone elses image for your own means without their permission, so no it doesn't avoid copyright. If anything it's worse because aside from using their image you're also stealing their bandwidth too. ZX81 ^talk 17:01, 24 June 2009 (UTC)

If nothing else you would be leaching their bandwidth. Bandwidth is not free and it may be costing them money to serve an image to your site. They might not appreciate that, to say the least.

They also might catch on that you're doing it, be angry, and change the filename of their image, and replace it with something else, possibly something obscene. APL (talk) 21:10, 24 June 2009 (UTC)

Yep. When I found that my designs were being used as backgrounds on myspace and the like, I redirected them to a little picture of a textbox saying something like "Did I say you could use my work and my bandwidth?". I'd have done differently if any of them had had the minimal courtesy to tell me, let alone ask permission. —Tamfang (talk) 17:30, 26 June 2009 (UTC)

Internet Connection drops out...a lot

Hola! It seems that, periodically, my internet connection (DSL) will spontaneously drop out. It's a simple fix, I just turn off my modem and turn it back on, then log back into my internet connection by configuring the "Basic Settings" on my (NETGEAR) router. But lately it seems to be happening more and more frequently. The other day it happened three times, and it's already happened once today. So my question(s) are:

What could cause my connection to randomly drop out like this. I do run Second Life most of the time, which is a known bandwidth hog. Is it possible that so much network traffic could cause my (modem/router/connection) to basically just say "Ok that's it, I need a break"? Or could it just be that my (modem/router) is old (modem is at least 5 years old), or there's some other problem with it. And if it's that, is it more likely that my modem or my router is the source of the problem? And if it's my modem, can you buy a new DSL modem at, like, a regular hardware store? Thanks so much for answering (in the future)! :) Digger3000 (talk) 18:28, 24 June 2009 (UTC)

In my experience heavy p2p use breaks a lot of cheap home routers. It shouldn't, but they all seem to run out of some internal resource (sockets, memory, io buffers, I dunno what) after a few days of it. Newer routers haven't, in my experience, shown themselves to be much better. Yes, you can certainly buy a new router at a computer store; Linksys, Belkin, and Netgear have much of the market, and make a dizzying array of router products. 87.115.17.119 (talk) 19:25, 24 June 2009 (UTC)

I've had 2 or 3 home routers break like this over the last 10 years and suspect the router has broken. Tempshill (talk) 22:28, 24 June 2009 (UTC)

If by "drop out" you mean that your wireless card reports no signal, it's the router (or the wireless card). Try upgrading the router's firmware to the manufacturer's latest version or to third-party firmware like DD-WRT. I switched a Linksys WRT54G router to DD-WRT and got noticeably better throughput and far fewer dropouts. -- BenRG (talk) 07:46, 25 June 2009 (UTC)

Does Windows Mobile have updates?

I have a PDA with Windows Mobile 2003 second edition on it. I was wondering if there are like regular updates for it like in Windows Update in the regular Windows. If so, where would I get such an update? I have no network connection on the PDA, so I would probably have to download it on my computer from somewhere, and then install it on the PDA over USB or something. --76.91.63.71 (talk) 20:20, 24 June 2009 (UTC)

No I'm afraid not. Windows Mobile 6 introduced "Windows Update" and the ability to download updates, although to date I've personally never seen any updates published (I suspect this is actually reliant on the provider of the ROM though and not Microsoft themselves). ZX81 ^talk 00:23, 26 June 2009 (UTC)

Recovering files "permanently" deleted in recycle bin

Note - moved from Misc desk

We all know that deleting things in the recycle bin on Windows doesn't truly delete it, but just marks the file as free space (or something like that). Question is, how do you retrieve the file itself? I've googled it before but a lot of the sites look a bit shady, so I was wondering perhaps if A) there was a way to retrieve the file without downloading software and B) if that isn't possible, what's a good free software tool? 97.126.198.46 (talk) 19:03, 24 June 2009 (UTC)

It is possible but it is not easy. The best way is to run a specific program that pulls specific "hidden" data that is marked on the sectors to have permission to write over the data. If you add data after you have emptied the recyclebin(including temp files from using windows) or defragment your OS then you will have more difficulty pulling the information. It sounds easy to accomplish however it is not and can be costly. Most programs out there on the internet free or not(mostly not) will not be able to pull most data if any from the OS. The short answer to your question is it is not possible. Unless the photos that disappeared are worth 10,000USD or more. Ivtv (talk) 23:58, 24 June 2009 (UTC)

A) No, you can't retrieve a permanently deleted file without downloading software. Unless you're some kind of super-wizard.

B) Yes, it's possible. Lifehacker lists 5 good quality freeware programs for Windows and explains how to use them. Indeterminate (talk) 00:03, 25 June 2009 (UTC)

I've used Pandora Recovery (free program) and found it to be quite effective. I'd recommend browsing download.cnet.com, a website of the non-shady variety :) . Seraphim♥ 00:24, 25 June 2009 (UTC)

OR you could use TuneUp Utilities undelete feature to recover your files. The software's not free though.... 117.194.224.3 (talk) 06:39, 25 June 2009 (UTC)

You can boot up Linux and then use ntfsundelete. That's free. --76.91.63.71 (talk) 06:50, 25 June 2009 (UTC)

Note that installing undelete/recovery software is likely to write over the previous storage location of the stuff you are trying to get back. Astronaut (talk) 13:26, 25 June 2009 (UTC)

Unless you install it to a different partition from the one you're trying to recover data from eg data missing from C drive, so install to D drive (if you have one!). Seraphim♥ 13:45, 25 June 2009 (UTC)

I've already recommended Glary Undelete, part of Glary Utilities. [Here's] the download link. It's freeware, works. Mxvxnyxvxn (talk) 21:53, 25 June 2009 (UTC)

Send me an email when a web page changes

Is there anything that will do this please? 84.13.164.184 (talk) 21:18, 24 June 2009 (UTC)

Yes. Google send e-mail when a website changes and several services will show up. Tempshill (talk) 22:29, 24 June 2009 (UTC)

You could also install something like Web Secretary on your own computer (requires Perl) and run it on a scheduled task/cron job. ZX81 ^talk 00:20, 26 June 2009 (UTC)

Image sizes changing when edited

Can anyone provide me with a short explanation of why jpegs are sometimes much smaller and sometimes much larger when edited? I've read the relevant sections of JPEG, libjpeg, Lossy compression, and Lossless data compression, but I still don't understand why the following actions produce the following results:

• I download a jpeg of this image with a 1-pixel-wide black border, remove the border but keep the white area with the caption, and it goes from 27,422 bytes to 6,477 bytes.
• I download this image, upload it as File:Anangula Site.jpg, someone crops it with Cropbot, and it goes from 24,717 bytes to 24,588 bytes.
• Someone reduces File:Ingrid Bergman in A Matter of Time.jpg from 370×250 to 300×202 to comply with the fair-use policy, and it goes from 12,044 bytes to 19,690 bytes.

Cropping a little bit and losing a little bit of size, like the Anangula photo, seems most natural, while the bits that I read about lossy compression make the church photo changes seem reasonable, but I can't see how the non-free size change happens. Perhaps most importantly — what's the difference? Is it just the program used? I used Windows Paint, although I don't know about the other ones. Nyttend (talk) 22:19, 24 June 2009 (UTC)

Apps that save JPEG images generally let you choose the "compression level" to use when saving, so the user can decide whether to sacrifice more image quality in order to achieve greater compression. Irfanview, for example, lets you choose a number from 1 to 100 to determine the quality level of the saved picture. If you choose 1, you are choosing the lowest quality in order to get the smallest file size. In your examples above, the users are likely saving the files with this number set differently than it was set to when the author of the picture saved the original file. Tempshill (talk) 22:26, 24 June 2009 (UTC)

Note that it is possible to losslessly crop JPGs with the right tools, albeit not with per pixel accuracy (it needs to be a multiple of the block size which is usually 16) as well as flip/rotate 90. If you don't need per pixel accuracy, this is a better option IMHO. Also note regarding tempshill comment that quality settings vary between programs/JPEG implementation. Certain implementations generally give better results then others for an equivalent size and 95 in one program is not necessarily the same as 95 in another program in other quality of size. There are also a bunch of other stuff you can do/choose which would affect quality and size. That is the nature of lossy compression, especially one as old as JPEG. Edit: I see cropbot is capable of lossless cropping. It's likely this was done in the example you gave Nil Einne (talk) 23:53, 24 June 2009 (UTC)

Microsoft Paint doesnt let you choose the quality setting and uses a pretty low one, resulting in reduced size and quality when you edit JPEGs with it usually. Note however, you choose a much higher setting and your file size increases significantly, the quality will NOT be improved, as the detail has already been permanently lost the first time it was saved as a JPEG. The best thing to do is to use a JPEG editor that will let you choose the quality setting, and choose the quality setting such the the kilobytes or megabytes per kilopixel or megapixel stays the same or increases slightly to be on the safe side. Some programs like Adobe Photoshop estimate the new filesize for you before you save the picture when you are choosing the quality setting. Roberto75780 (talk) 05:15, 25 June 2009 (UTC)

In the two images from nps.gov that you linked, only about 30% of the file size is the actual JPEG data; the other 70% is cruft added by Photoshop. This includes a 3K embedded thumbnail, a second 3K thumbnail identical to the first, 6K of "tone reproduction curves", and 4K of ASCII spaces in an uncompressed XML document. Some image editors will strip all that from the output and others will preserve it. -- BenRG (talk) 06:48, 25 June 2009 (UTC)

Upgrading windows 1.0 to vista. Is this possible?

I have a pondering question. Is it possible to upgrade from X to vista? X being the earliest version possible to vista. I always wanted to try it but I could never be bothered to get all the legal copies of all the operating systems. It would have a few strange results like your boot.ini file (up to xp) having full control of your registry and some kernal issues(if you can even upgrade from pre NT to NT) but can this be done? If you know the answer can you please explain in full the situation or where the cut off is? any one try it?

I do not mean a format. I mean "upgrade". Thanks Ivtv (talk) 22:43, 24 June 2009 (UTC)

An update licence for Vista will only update XP. 87.115.17.119 (talk) 22:49, 24 June 2009 (UTC)

Would it be possible to find a computer that would run both such an old version and such a new version? Nyttend (talk) 22:57, 24 June 2009 (UTC)

thank you for the information 87.115.17.119 however I believe you are incorrect or maybe I was unclear. I know from experience you can upgrade windows 2000 to xp, then upgrade windows xp to vista. what I am asking is, is it possible to upgrade from windows 1.0 to 2.0 then to 3.0(or 3.1 which was the official release I believe). From there, insert your windows 95 upgrade floppies. then windows 98. after upgrading to windows 98, upgrade to windows ME. then upgrade to windows 2000, then to XP then to vista. The only issue I can see here is the Pre NT kernal when ms dos ran the back end for windows and windows was a GUI only.

Ivtv (talk) 23:28, 24 June 2009 (UTC)

I think that the Windows 2000 upgrade would just check C:\ to see if there was a COMMAND.COM there. (Presumably it did some kind of checksum or CRC to verify it was a Microsoft-published command.com.) That would shorten the number of steps. But this is based on my memory and not a verifiable source, sorry. Tempshill (talk) 01:56, 25 June 2009 (UTC)

The early Windows were not Plug and Play, but required separate drivers for peripherals. This meant a hard drive could be removed to a quite different machine, and Windows would work on it straight up. From Win95 on, drivers were included for registered perihperals (so they still need drivers, but these were built in to the operating system). At this point, the familiar "found new hardware" message started popping up if a hard drive was moved to another machine, as the OS started using drivers for motherboard components as well.

This means Windows 1.0 would probably work on a computer new enough to run Vista (if you can find one with a floppy drive). But Vista would not run on a machine designed for Windows 1.0 ( 286, anyone?). But going through all the steps, you should be able to upgrade from Win 1.0 to Vista if you have a few days to spare. You would probably get from Win98 to XP without going through ME and 2000.

Oh, you'd have to have the right versions of DOS under the old Windows, too; Win 3.0 is not going to run over Dos 2.0 -- which came on 51/4 in. floppies so you'd to copy them to 31/2 somewhere. You couldn't copy it to CD because you'd have no CD support without a driver diskette until you hit Win95, and your Vista machine CD won't have a Win 3.0 compatible driver.

Don't be surprised if the pre-load memory check reports negative amounts of memory, when a program designed for 4Mb tries to check 4000. If it causes problems, just comment out the memory-related lines in the autoexec.bat.

Just for curiosity, why would you want to do this? - KoolerStill (talk) 06:50, 25 June 2009 (UTC)

Thank you for the informative response. So the short of it, It is possible, but requires a lot of work. You ask me why? I ask why not. Something to do. Just to say I did it. Ivtv (talk) 21:25, 25 June 2009 (UTC)

Sorry I know I'm a bit late here, but I believe you'd also have some disk partitioning issues. Assuming Windows 1.0 will actually run on MS-DOS 6.22, that version of DOS only supported FAT-16 which is limited to 2Gb partitions, something Vista physically won't fit in. Although Microsoft do support resizing disks in the later versions of Windows, the conditions are that disk/paritions were created as dynamic in the first place. Because you'd have to "keep" each version for it to be an upgrade (and not blow the disk away), strictly speaking I can't see it being possible without using 3rd party tools. ZX81 ^talk 23:56, 25 June 2009 (UTC)

If you're going through all of these different Windows versions, why stop at Vista? Why not go for the Windows 7 beta? PCHS-NJROTC ^(Messages) 06:27, 26 June 2009 (UTC)

I know I'm late as well, but heck, why not try this in a VM instead of on a physical computer? Rgoodermote  18:42, 27 June 2009 (UTC)

Haha thanks for the replies here. Yeah, we could include windows 7, but it is not released yet. When it is released in october I will add it to the list but I just see windows 7 as a glorified vista that is a glorified XP. the user ZX81 was very helpful as well seeing how I would need to use 3rd party tools. Going to be an adventure for sure. Noone else has attempted it that I know of. Someone has to try it. I could try a VM as well. Open to opinion, I just want to see the explosion,yet still have it work :) Ivtv (talk) 02:35, 1 July 2009 (UTC)

Common units for (semi)proffesional desktop publishing?

Using an Adobe InDesign trial, I notice that measurements are in the form of 00p00 (with a p in the middle of some numbers. What units are these? ----Seans Potato Business 22:44, 24 June 2009 (UTC)

Picas and Points. You can change this in the document preferences or change the default by closing all documents and change the preferences. ---— Gadget850 (Ed) ^talk 23:17, 24 June 2009 (UTC)

How long can I submerge my keyboard in water before it's damaged (assuming damage is even possible)?

I eat a lot at my computer desk and two of my keyboards have keys that stick. To try to clean them, I have submerged them in water in my bathtub. From my experience of accidentally leaving a USB drive in the pocket of my pants and washing them in the washing machine, my understanding is that electronic equipment should be fine as long as I wait until they're thoroughly dry before electricity flows through them. My question is this. Is it safe to leave the keyboards in the bathtub the whole night or is it possible some part of the keyboard will be damaged from the water? A Quest For Knowledge (talk) 22:51, 24 June 2009 (UTC)

I clean keyboards from time to time. I remove the case, clean with water and a spray cleaner, drip dry for a few hours, spray thoroughly with denatured alcohol and then dry for a day or so. If you are not cracking the case, then let it dry for a few days and rotate it ever so often so the water drains. ---— Gadget850 (Ed) ^talk 23:10, 24 June 2009 (UTC)

The keyboards I've opened up and looked at contain two layers of flimsy plastic with metal tracks printed on, a keystroke consists of pressing one layer against the other to make a contact. Water could get between these layers, so if you want to dry it out, you'd have to take the layers apart to make sure there isn't any water left there afterward. They can corrode inside, as I discovered when repairing a keyboard recently: a drink spill had apparently stopped one of the metal tracks conducting, and I had to solder a little bit of wire over it. 213.122.17.108 (talk) 23:21, 24 June 2009 (UTC)

If you are talking about DESKTOP keyboards then yopu can just remove each key and put it in a bag with some non abrasive cleaners like liquid dish detergent. then shake out the skin particles and the food particles from the keyboard chassis itself and flean it with a cloth or something smaller. after the keys dry put them back on. I do this once every 6 months and it works fine

Ivtv (talk) 23:34, 24 June 2009 (UTC)

Yes, it's a desktop keyboard. It's already in the bathtub soaking. My question is really should I let them soak overnight or is there some material in the keyboard that would be damaged if submerged in water for 12-14 hours. I once ran water from my sink's water faucet into a keyboard, but that was for only a couple minutes. I'm just wondering if I should take them out of the bathtub tonight before I go to bed or tomorrow morning? A Quest For Knowledge (talk) 23:59, 24 June 2009 (UTC)

The length of the soak shouldn't make a lot of difference as long as you don't have a lot of metals in your water that can collect on the keyboard. Even calcium deposits can mess up electronics. The key is to clean it thoroughly with alcohol (rubbing alcohol will do) after it is soaked. The alcohol will evaporate very quickly, leaving a nice dry keyboard. Please note that if the keyboard was broken before you cleaned it, cleaning it will not always fix the problem. -- kainaw™ 00:20, 25 June 2009 (UTC)

I'd say leave it in - (nobody has mentioned rusty springs yet - some keyboards have steel springs in the keys which do rust - not that that would break it - but..)

Personally I like to use a hand hot shower to clean electric stuff - could be worth considering for those hard to reach places.

There's nothing I can think (in a keyboard) that would be damaged by an overnight soak - more problematic is getting all the water out - especially membranes etc, + the potential of rust - which is greater when drying (exposed to the air) rather than when submerged.

Another tip - using water from the hot tap - no cold - not only does it have better cleaning power, but if you let the whole device become hot from the water before removing it you'll find that the heat causes a lot of the water to evaporate soon afterwards, greatly reducing drying times.

This [1] for extreme keyboard cleaning. Recommended..83.100.250.79 (talk) 00:24, 25 June 2009 (UTC)

After all that, a layer of cling-wrap over the keyboard, replaced weekly, would stop further problems, if you don't want to invest in a custom keyboard cover at twice the price of the board itself.- KoolerStill (talk) 07:01, 25 June 2009 (UTC)

The first think I do with a keyboard that is having problems is try blowing round the key with a can of compressed air and turning it upside down. That often cleans things up without need needing to remove keys or wash and dry. I don't think soaking for a long time is going to do any better at cleaning than a quick wash but I can't see it doing any harm either. You want to wash the dirt away not make it swell and grow larger. Dmcq (talk) 08:19, 25 June 2009 (UTC)

Rust