Wikipedia:Reference desk/Archives/Computing/2011 December 29

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December 29[edit]

Is there a way to send a two-way anonymous email?[edit]

I'd like to send an anonymous email without the recipient to know who I am, but would still like to be able to get a reply from him. Will anyone suggest any service that allows this? Thanks. -- (talk) 01:45, 29 December 2011 (UTC)

Sign up for any of the many free web-based email services. Create an account. Send the email. Check the account to see if you get a reply. -- kainaw 01:53, 29 December 2011 (UTC)
See Comparison of webmail providers. If you don't want to check the account periodically for a reply then look for a provider with email forwarding (assuming you have a non-public email account you check anyway). PrimeHunter (talk) 02:04, 29 December 2011 (UTC)
Once upon a time, there used to be a service that would forward encrypted e-mails in "hops" between various servers. At each hop, a level of public-key encryption would be removed. Only the final server could figure out the actual destination of the mail (and did not know where the mail originated). I am not sure whether there was any provision for the recipient to send a reply; at the moment I can't see how to do that in a way that doesn't significantly reduce the sender's protection against being identified. I also don't know whether the service still exists. --Trovatore (talk) 02:15, 29 December 2011 (UTC)
Oh, I guess you could include a multi-encrypted return address that had to "hop" back to the original sender, being decrypted along the way. As long as the servers themselves are not forced to reveal anything, that seems reasonably secure, barring traffic analysis. --Trovatore (talk) 02:22, 29 December 2011 (UTC)
Pseudonymous remailers are what you're looking for. As far as I know they still exist. -- BenRG (talk) 05:14, 29 December 2011 (UTC)

locate an iPod[edit]

My daughter has an ipod4 that is synced to iTunes on my computer. She can't find it, but she thinks that there is a way to locate it with the iOS app icloud, or something like that, to make it play sounds. She can't find how to do it in iTunes. Is there a way to do this? Bubba73 You talkin' to me? 03:06, 29 December 2011 (UTC)

This page at Apple describes how to "find my iPod". RudolfRed (talk) 03:33, 29 December 2011 (UTC)
It says that it can make a sound, but it doesn't say how to use it (to make a sound). We know it is somewhere in the house. She set up icloud on my computer the other day, but she doesn't know how to access it. Bubba73 You talkin' to me? 03:59, 29 December 2011 (UTC)

From the sound of the above link, you may not be able to push 'Find My iPod touch' so you may not be able to use that method if you didn't already install the program in the ipod touch Nil Einne (talk) 15:54, 29 December 2011 (UTC)
She got this iPod a few days ago, and (fortunately) the software was already installed on it, so she just had to log in to icloud to make it make a sound, and she found it.
Bubba73 You talkin' to me? 16:35, 29 December 2011 (UTC)

Project Gutenberg and google books[edit]

Hi, if a book is in the public domain, are project gutenberg and google books equally easy for downloading, or...? Since project gutenberg only has 100,000 books according to its website, and google books is huge, what does gutenberg do that googlebooks doesn't? Thank you. Richard Peterson76.218.104.120 (talk) 03:43, 29 December 2011 (UTC)

Gutenberg scans and OCRs, and then has humans exhaustively proof-read - see distributed proofreaders. Google scans and OCRs, and not much else. The best one-stop-shop (for me) is the Internet Archive, which grabs all of the PD books from google, gutenberg and other places, and makes them available in a range of formats. --Tagishsimon (talk) 03:48, 29 December 2011 (UTC)
PG also makes it easy to download in text format, while Google books only supports online viewing or PDF. If you want to reformat books, read them on mobile phones etc, perform textual analysis, quote long passages, or do a search through a book's text, Gutenberg's text format may be better.
Also, Project Gutenberg has been going for about 30 years longer than Google books. --Colapeninsula (talk) 16:15, 29 December 2011 (UTC)
thanks everyone. If i get an old Kindle 1, which, or all, of PG, Google, and Internet Archive will I be able to get on my kindle screen? (talk) 01:35, 30 December 2011 (UTC)
Take a look at the Amazon Kindle article. The old Kindle 1 supports "unprotected Mobipocket books (MOBI, PRC), plain text files (TXT), Topaz format books (TPZ), and Amazon's format (AZW)" although third-party software can "convert PDF and other files to the first-generation Kindle's supported formats". Astronaut (talk) 02:23, 30 December 2011 (UTC)
I don't know what those acronyms are or mean. Will Kindle 1 get google books , internet archive or project gutenberg? (talk) 04:50, 30 December 2011 (UTC)
Gutenberg should work. Many books are downloadable as "Kindle format" directly from Gutenberg. For the rest, you download some other format like HTML and then use a program like Calibre (software) to convert to Kindle format. For Google, it might be harder. Later Kindle versions that support PDF can read Google books, though without repaginating (works best if the page size is small or you have a Kindle DX) Jørgen (talk) 08:49, 30 December 2011 (UTC)
It should be noted that if the book has just been OCRed and not edited, it will appear as a big mash of nearly unreadable text on the Kindle. It's a pain; it's usually unreadable. I find most of the Gutenberg books I've used to show up OK on the Kindle when downloaded as .MOBI files. The formatting is usually a bit off but it's usually not awful. Sometimes the formatting is really off (each sentence has physical line breaks on it which means you get all sorts of jagged paragraphs on the Kindle) but it is still readable. With Google Books I have not had good luck at all other than as PDFs, which I find nearly unreadable on the Kindle's screen (you can't really zoom in to the right level, and it requires a lot of work to navigate around a PDF page on a Kindle). So my experience is that Gutenberg is pretty good for Kindle books — not perfect, but pretty good — and Google Books is generally not at all. I imagine Google Books would be more useful if you had something like an iPad, which is a larger format and has an interface for manipulating PDFs which is better thought-out than the Kindle's. --Mr.98 (talk) 13:47, 30 December 2011 (UTC)
Let me just note that Google Books now offers at least some PD books in EPUB format, which is supported by many e-readers, although not by any of the Kindles. Looie496 (talk) 16:06, 30 December 2011 (UTC)
Wow, thank you everyone. This is very helpful. Rich Peterson76.218.104.120 (talk) 06:13, 31 December 2011 (UTC)
Google's PD EPUBs should be convertible to MOBI (which Kindle can read) using e.g. Calibre (software) as mentioned above, as long as the EPUBs don't have digital rights management enabled (which they likely won't, since they are public domain). Calibre can also convert PDFs to MOBI, but with very variable success depending on the structure of the PDF (I have seen PDFs which work perfectly when converted, and ones which put every single letter on a separate line). Equisetum (talk | contributions) 21:02, 31 December 2011 (UTC)

Mouse audio sound missing[edit]

I have Toshiba Satellite laptop with window 7. My computer doesn't give a click sound at all when i click files and folders to open and close them. I tried everything. Laptop is in good condition and speakes work very nicely accept that volume is very low even if its 100 percent volume. But mouse click never seemed to happen on my computer. click sound works only when i go to control panel window. Doesn't matter how many changes i make but mouse doesn't give a sound :( — Preceding unsigned comment added by (talk) 04:54, 29 December 2011 (UTC)

Maybe it's just too quiet to hear ? Try plugging in headphones, as that might make it louder. You can also plug in external speakers, but obviously those aren't very portable, so best to use those at home. StuRat (talk) 05:01, 29 December 2011 (UTC)
I don't recall that file/folder open/close are events that can be assigned a sound, but I'm not near a Win 7 system right now. You can look at and modify your current sound scheme by following the instructions here. --LarryMac | Talk 15:29, 29 December 2011 (UTC)
Perhaps that sound (when you click on something) needs to be set up on your computer. (I'm working on Vista so Win 7 might be different, but this is how you turn it on...) You can go to the 'Sound' applet on the control panel and pick the 'Sounds' tab; scroll down to the 'Windows explorer' group and check if there is a little speaker next to "Start navigation" and "Complete navigation"; if not, you need to add a sound from the list of sounds in the drop-down list. You can use the 'test' button to try out the sounds (perhaps to check the volume is sufficient). Astronaut (talk) 02:12, 30 December 2011 (UTC)

Reusing an old wired router to get more Ethernet ports in the home network[edit]

My main wireless router (#1) for the home is running out of Ethernet ports. Since I have an unused wired router (#2) lying around, I want to know how I can use it to make a few more Ethernet ports available for wired networking. I thought about a cascade NAT configuration, but the devices on the main LAN would not be able to talk to devices behind the newly added router #2.

What is the right way to do it?

Should I connect the WAN port of router #2 to a LAN port of router #1, turn off NAT on router #2, and add a route to router #1?

Should I turn off NAT & DHCP on router #2, and connect a LAN port of router #2 to a LAN port of router #1?

Should I do something else?

Thanks. — Preceding unsigned comment added by (talk) 07:40, 29 December 2011 (UTC)

"Should I turn off NAT & DHCP on router #2, and connect a LAN port of router #2 to a LAN port of router #1?" Depending on the type of router, this option should work. I suggest that you try this first. (talk) 11:20, 29 December 2011 (UTC)


i,m trying to write a spider with python, but i ran the following script:

import urllib
for v in a:
   print v
print 'done'

and one line said "access denied" if anyone can tell me how to fix it, that would be great. thanks, Jake1993811 (talk) 10:16, 29 December 2011 (UTC)

Do you have an internet proxy server between you and the web (you should be able to tell from the settings for your web browser)? You will probably have to tell perl to use the proxy; I can't remember how urllib works but there should be an option. --Colapeninsula (talk) 16:17, 29 December 2011 (UTC)

Using python 2.7, I tried this and also got an error. The page returned to me included:

Our servers are currently experiencing a technical problem. This is probably temporary and should be fixed soon. Please <a href="" onclick="window.location.reload(false); return false">try again</a> in a few minutes.


If you report this error to the Wikimedia System Administrators, please include the details below.

Request: GET, from via (squid/2.7.STABLE9) to ()

Error: ERR_ACCESS_DENIED, errno [No Error] at Thu, 29 Dec 2011 19:20:24 GMT

If I use the same code for other websites, they produce the expected content.-gadfium 19:36, 29 December 2011 (UTC)

The error message is a lie. And I mean that not in the slangy "computer program said something that doesn't apply in context" sense, but in the more traditional "a person deliberately told something untrue to prevent you from knowing the truth" sense. It's User-Agent discrimination. Look up how to change the user agent in the urllib documentation. Set it to Mozilla/5.0 and things will be all right, at least until that moving target moves again. And please configure all your other http clients to send random, false, or non-existent User-Agent headers as a protest against the shitty behavior of server admins who do this. (talk) 23:41, 29 December 2011 (UTC)

thank you all. i,ll try that. Jake1993811 (talk) 02:41, 30 December 2011 (UTC) p.s: thanks for fixing the code snip — Preceding unsigned comment added by Jake1993811 (talkcontribs) 04:36, 30 December 2011 (UTC) thanks, it was the User-Agent headers. and the python docs say you also can't use "uncommon browsers". urge to kill: rising... — Preceding unsigned comment added by Jake1993811 (talkcontribs) 05:43, 30 December 2011 (UTC)

I've certainly learned something.-gadfium 07:49, 30 December 2011 (UTC)

There's a rich API with implementations in many many languages, including Python (mwclient (docs)). Scraping and parsing the HTML rather than using the API is, in 99% of cases, the wrong thing to do. -- Finlay McWalterTalk 12:25, 30 December 2011 (UTC)

Just to explain why this "error" exists... When Wikipedia started, everything was fine. Then, some kids who had more time than programming experience decided to use scripting languages like PHP and Python to spam as many pages on Wikipedia as possible with vandalism. So, Wikipedia was set to ignore requests that do not have a header that appears to be a web browser. It is't a real problem. Anyone who knows how to program will likely use something like curl to access Wikipedia anyway. It only affects those that really aren't experience in web-programming. It creates a wall: Learn how to actually fetch and parse html before you start messing with Wikipedia. Most people do not feel that this wall is a bad thing. -- kainaw 14:31, 30 December 2011 (UTC)

kainaw, what evidence do you have that it was kids? also, meny other sites do this also. and i can see why. Jake1993811 (talk) 23:19, 30 December 2011 (UTC) i changed the user-agent header, now it say the server severed the connection., if you have advice, that would be great. and someone tell the server admin hes an a**hole. Jake1993811 (talk) 03:57, 31 December 2011 (UTC)

>>> import urllib, urllib2
>>> useragent = "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.2 (KHTML, like Gecko) Chrome/18.6.872.0Safari/535.2"
>>> contenttype = "application/x-www-form-urlencoded"
>>> url=""
>>> request = urllib2.Request(url=url, headers={"User-agent":useragent, "Content-type":contenttype})
>>> for x in urllib2.urlopen(request): # Alternatively, use ""
... 	print x

That works for me. What exactly did you do? →Στc. 04:22, 31 December 2011 (UTC)

I used "kids" because I thought someone might be offended by "script kiddies". -- kainaw 14:12, 3 January 2012 (UTC)

thanks Σ, your code worked great. not a problem Jake1993811 (talk) 00:48, 4 January 2012 (UTC)

getting started with paypal[edit]

So, how do I actually paypal for something I bought on the internet. Paypal itself has sent me an email with the details of how much I need to pay and what for, and a big button saying Pay Now, going to that, I had to create a paypal account, but that done, going to the email button again, it comes up with my new account, which is empty, there is no mention anywhere of the money I owe, just a series of lists with nothing on and a few blank forms. What do I do now, then, to actually send this money? Surely this was supposed to be the easier way of paying for things, it really doesn't look it from here.

The only thing I can find anywhere near resembling an opportunity to send money is a form to pay someone, for which I would need to know various details including their email address, which I don't have, and I suspect this would be sent separate to the original payment demand, leaving that not marked as paid off. (talk) 11:09, 29 December 2011 (UTC)

You may have to send a payment to the email address. (Can you contact the person who you need to pay?) Is this for an eBay/auction sale, or to an online store, or a gift to a private person? Some online stores will have a connection with a form to the PayPal site, but often with eBay sellers and private individuals you have to send the payment to their email. --Colapeninsula (talk) 16:20, 29 December 2011 (UTC)

It's on a site similar to ebay but a bit smaller, I now have the email address of the person I need to pay, so I can send the money that way, but what I want to know is, if I instruct paypal to send him the money, would it mark my payment request as sent? since they are selling lots of these, how would they know which ones had been paid for, there isn't anything I can see to link my paypal account to my particular order details (talk) 16:48, 29 December 2011 (UTC)

OK, so now Paypal is being even more horrible than before, apparently to pay for something, I need to verify my account by linking it not just to my card, but also to my bank account, except that where I already tried to link it to my bank when first attempting to create an account, and then found that I would have to wait some days for that to be confirmed, I gave up and went with just paying by card. What this apprently means, though, is that I cannot link and verify my account until after my other attempt is finished, that is until I manage to find out how to sign back into the half created account, which is no longer possible, and wait thosw few days for confirmation, which is longer than I have to pay this money. The alternative is to transfer funds to my paypal account, which also takes some days. What happened to the idea that this was a much quicker and easier method of paying for things?

How do I fix this? How can I get it to stop attempting to confirm my other account attempt, verify this real account and let me send this person the money? All I want to do is pay them, it should not be so hard, right? (talk) 17:13, 29 December 2011 (UTC)

OK, forget all that, problem solved, it turned out both times I had tried to activate the account through my email, it had not bothered, but the third time, it worked suddenly, and there it all is, fixed just like that. Thanks for your help. (talk) 17:34, 29 December 2011 (UTC)


my pc swaps always on the hd[edit]

even if the sum of the sizes of the processes is less than the RAM amount.. any idea? thanx -- (talk) 14:35, 29 December 2011 (UTC)

I'm a bit confused by your question. Are you asking why your OS swaps data out of RAM to the HDD even when there is more available then in total use by programs or why your OS has a swap (or page in the case of any Windows NT) file even when there is more available RAM then in total use by programs? For the second case, most OSes prefer to keep the swap file both to ensure there is alway enough space for it and to reduce fragmentation. As for the first case, with any OS, there's always some conflict between deciding whether to cache data which may be needed in the near future in RAM or keep program data in RAM which hasn't been used for a long time and may not be needed for a long time. I presume some OSes also preemptively copy of program data to the swap or page space while preserving it in RAM ensuring it can easily be reallocated if necessary, whether for RAM or cache data. (Remember unlike with cache data, you can't simply delete program data if you don't have a copy.) Recent versions of Windows are generally considered fairly aggressive in swapping out program data and you only have limited control. With various *nix OSes I believe you have far greater control over how aggressive the OS is. However before you get too concerned are you actually noticing problems, e.g. it's taking a long time to go back to old programs? If the only effect is in some system monitor, I suggest it's best to stop worrying about it. Nil Einne (talk) 16:16, 29 December 2011 (UTC)
As a fairly belated note [1] and [2] appear to confirm what I said, Windows tried to keep a copy of everything in RAM on disk (in the page file when necessary, obviously for cache there is already a copy) so it can easily free up memory. Nil Einne (talk) 13:50, 11 January 2012 (UTC)
The operating system can page out unused stuff even if it doesn't need memory right now, in anticipation of needing it later. Also, memory use is not simply a sum of process sizes, as memory contains other things, such as the operating system kernel and its data structures, network buffers, and (as a rather large item) cached disk data. If some part of a process hasn't been touched in a long time, it may make sense to page it out so that more file data can be cached in memory. (talk) 16:25, 29 December 2011 (UTC)
If it is a Windows system, be sure to let Windows manage the Swap file. This is in the system settings somewhere. Bubba73 You talkin' to me? 18:29, 29 December 2011 (UTC)

FoxTabPDF Converter[edit]

I am trying to download "FoxTabPDF converter" from However, at the end of the installation I keep getting the message "Printer installation error 1601". How can i find out what this means and how can I successfully download this program? — Preceding unsigned comment added by Ralphbrighton (talkcontribs) 18:13, 29 December 2011 (UTC)

Hmm, I don't know the program, but I'd be marginally wary of it. A Google search on it returns most of the top ten results suggesting it may be malware. Per this Mozilla support post this is not a recognised Firefox add-on, and there are a number of established PDF convertor programs; I'd be inclined to go for one of them (I mainly use Acrobat Professional myself, but have successfully used CutePDF on many occasions). --jjron (talk) 09:37, 30 December 2011 (UTC)
Do not use FoxTabPDF. You can find an alternative here. Von Restorff (talk) 09:28, 3 January 2012 (UTC)