Wikipedia:Reference desk/Archives/Computing/2011 July 14

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July 14[edit]

sprint and text/sms costs?[edit]

Hey, im using http://www.textem.net/ to communicate with a friend. They have sprint. according to one of the responses here http://sms411.net/2006/07/sprint-sms/ sprint has really bad service switching from email to phone, which i THINK textem uses... maybe they somehow send a message directly? not sure.

Anyway, i'm having big issues with my messages not going through, and also with not getting messages from my friend. I dont know if its the site or sprint or both.

If i text them using email (######@messaging.sprintpcs.com) will i get better service? will it cost them where textem doesnt?

I just want to find a way to text RELIABLY for free, hopefully not costing my friend either. Is this possible? Opinions and any pertinent info please!

Thank you very much! 172.163.26.218 (talk) 02:56, 14 July 2011 (UTC)[reply]

Macbook hardware diagnostics (memtest, disk drive)[edit]

I am trying to help a friend who has a Macbook Pro with an Intel processor. I'm trying to install Mac OS X Snow Leopard, but it hangs in the middle of the install.

If this were a PC I would load up Ultimate Boot CD for Windows and run memtest86 and a hard drive test, but I obviously can't do that on a Mac.

During the install, I have tried to erase and reformat the hard drive, that does not help. I have run the verify and repair tools on the hard drive, that doesn't help either (they both 'pass').

Q: How can I diagnose problems with either the memory or disk drive on a Mac, if I can't boot into the operating system?

Thanks, TheGrimme (talk) 03:47, 14 July 2011 (UTC)[reply]

Memtest86 will run on a Mac. Download an ISO of it and give it a whirl. --Mr.98 (talk) 03:54, 14 July 2011 (UTC)[reply]
Thanks Mr.98. I burnt the iso and tried booting with it. Doing nothing, the disk spun but the computer just showed a picture of a folder with a question mark. I found a youtube video that said to hold alt, and instead of that image it remained at the gray screen with an arrow for a cursor. Either way, it didn't seem to want to boot with memtest. Any ideas for memtest? Any ideas for testing the hard drive? Thanks again, TheGrimme (talk) 05:11, 14 July 2011 (UTC)[reply]
Do you have an OS X DVD? I would try to boot from that. There is a hardware diagnostic program on the DVD as well. --Mr.98 (talk) 14:44, 14 July 2011 (UTC)[reply]
I do have the OS X Snow Leopard retail DVD, but not the hardware testing disk that (after reading many forums) apparently comes with an Apple computer when you purchase it. The only tool the DVD gives me is the disk utility, which after 4 seconds says the disk is fine. This is not an accurate disk check. — Preceding unsigned comment added by TheGrimme (talkcontribs) 18:18, 14 July 2011 (UTC)[reply]
You should be able to get the original OS X disk that came with the machine from Apple, if it has been lost. Even if your support contract has expired, the Apple help line might give you some ideas. You did not say what OS is currently on the machine. If you can get the OS X disk that came with the machine, you can boot from that, regardless of the state of your hard disk. EdJohnston (talk) 18:59, 14 July 2011 (UTC)[reply]

How do I forcibly move some stubborn Android apps onto the SD card?[edit]

On my Sony Ericsson Xperia Play, I only have 380 MB of internal memory. I remember when 380 MB was a LOT (alas, that was in 3rd grade.) However, I have gigs on my SD card.

The only problem is, some apps won't let me move them to SD cards and I'm running out of room. Therefore,

  1. How do I forcibly get those said apps onto the SD card anyway?
  2. How do I swap out the internal 380MB card for a bigger one, and transfer all the internal data to the bigger one?
  3. Being low on internal space, will new apps download directly to the SD if they're eligible for it? (Or do I have to manually change something to let that happen?)
  4. On the Android market, how do I tell whether the apps are eligible for the SD card?
  5. Is there an app that removes the stubbornness of those apps that normally won't let me move them to the SD card, by way of somehow changing that particular permission?

Having hoarded hundreds of fine apps, now would be a great time for epic assistance. --70.179.165.67 (talk) 03:54, 14 July 2011 (UTC)[reply]

There are some apps that will force other apps to an SD card. When an app is made, the programmer decides if it will be allowed to move to the SD card. For development, you can move things around. So, you get a developers app and put that on your phone and you can do things that a normal user cannot do. This is not completely rooting the phone - it is just a developer tool. Unfortunately, not all apps will work properly if run from the SD card - especially if the SD card didn't initialize properly when you turned on the phone (a common problem). Most of these apps that allow this environment have names like SDMove or SDForce. Also, they tend to be ones you have to download, compile, and install yourself.
I haven't seen an Android phone yet that allows you to alter the internal storage in any way. You can only change out the SD Card. Even the Droid Global (which allows a lot of hand-on) doesn't let you get to the internal storage without mutilating the phone.
As with the "move to SD card" apps above, there are developer's tools which force everything to the SD card. They tend to be called things like App2SD. Again, they usually require you to download, compile, and install them.
I do not see anything in the App store which allows you to see if an app can be moved to the SD card. I just uninstall the stupid ones that can't do SD card (like the new Google+ Android App - you'd think that Google would be able to make a good app).
The last question is a repeat of the first question. -- kainaw 12:53, 14 July 2011 (UTC)[reply]

USB gamepad on Linux[edit]

I'm running Ubuntu 64 Natty, and have installed a cheap gamepad with two axes on an 8-way d-pad (not analogue) and 10 buttons. I'm having a few problems.

  • First, the number of axis registering in Linux is 6, not two, and the two axis that exist are not the first two that Linux acknowledges.
  • Second, even after remapping the two axes that actually exist to 0,1, although the gamepad appears to work in jstest, neither of the games with which I've tried it acknowledge my use of the d-pad. Presses on any of the buttons are recognized, but not the axes.

Any ideas?--Leon (talk) 14:13, 14 July 2011 (UTC)[reply]

mod_rewrite and .htaccess help[edit]

I'm trying to set up an .htaccess file with mod_rewrite that will take all traffic and shoot it to one page.

So let's say I have http://mysite.com/index.php, which is my main "controlling" page. If you go to http://mysite.com/blah/hello.html (or any other subpage query of mysite.com), I want it actually to load up index.php, but not change the URL path as far as the browser is concerned. index.php will then analyze the URL string and serve up content appropriately.

My gut says mod_rewrite is the way to do this, but really, I've got no clue how to use it correctly. Seems like a lot of regex strings and I'm not too keen on those.

Anyone have experience with this who can lend a hand? --Mr.98 (talk) 15:06, 14 July 2011 (UTC)[reply]

Nevermind, I figured it out. The Wordpress htaccess settings here did the trick. --Mr.98 (talk) 16:18, 14 July 2011 (UTC)[reply]

Fake PayPal email[edit]

I am in the UK. I've got an email suppopsedly comming from PayPal. However the "from" address has nothing to do with PayPal, and the link I am asked to click on redirects to a web address that ends in .tw.

What should I do about it or with it, if anything? I've already marked it as junk mail. 92.24.177.241 (talk) 18:41, 14 July 2011 (UTC)[reply]

Just delete it and ignore anything similar, its common for spammers and scammers to send fake emails claiming to be from banks and whatnot in an attempt to get you to give them your details.--Jac16888 Talk 18:43, 14 July 2011 (UTC)[reply]
But, how do they fake the email address? I sometimes receive the email with exactly the address of a real bank (like clientservice@realbank.com) not a thing near it (like clientservice@realbank.tw). Quest09 (talk) 21:15, 14 July 2011 (UTC)[reply]
An email is just a text file. At the top are some email headers, which are just name:value pairs. Any email library lets you set the values to all of these, and make up any old ones you like. As the mail is moved around between mail servers they often add other stuff (the route it took, whether that server thinks the email is spam, etc.) but stuff like From: and Date: are rarely touched. So it's trivial to set a From: to read as anything you want; it's also common to manipulate the date: to either be in the future or the distant past (so it's at one end or other of the recipient's email list, if it's sorted by date). -- Finlay McWalterTalk 21:23, 14 July 2011 (UTC)[reply]
(edit conflict) They fake it by tampering the "From:" header that indicates the sender, which is read at face value by your email client. That can be thwarted by verifying the header with a public key from your bank, but it is a pain to do if you're a normal user (actually, it is a pain to do not matter how experienced you are). With these things, the best thing is to be skeptical, and exercise caution with emails regarding your bank. Don't click on links included on the email, and contact your bank if there is something particularly suspicious - frankie (talk) 21:25, 14 July 2011 (UTC)[reply]
(The technique is known as E-mail spoofing.)--Kateshortforbob talk 22:12, 14 July 2011 (UTC)[reply]
I have an e-mail here & I know who sent it both from the "from" address & by the content. But suppose I get an e-mail apparently from the same person at the same e-mail address. If something in the content makes me suspicious as to whether they sent it, would comparing the two headers establish whether the new email is fraudulent? Thanks, Wanderer57 (talk) 23:25, 14 July 2011 (UTC)[reply]
It depends on how well the spoof is made. If they only changed the "From: " header, then you could compare the other headers for clues on whether it is legit, but those headers may be altered just as easily. In the scenario you present, you have the option to contact your friend to confirm if the email is from them, but then it could happen that that communication channel could be compromised as well, so a new approach would be required. Regarding IT security, there is always a degree of speculation and uncertainty, regardless of any measures taken - frankie (talk) 13:32, 15 July 2011 (UTC)[reply]
I once got a fake PayPal e-mail which had even copied PayPal's warning "If in doubt, write the address to your browser by hand instead of clicking on links" verbatim. A self-defeating scam e-mail! =) 194.100.223.164 (talk) 09:43, 15 July 2011 (UTC)[reply]
Quite in contrary. They look more reliable doing that, since people dont expect scammers to use such sentences. They are reducing the "doubts". — Preceding unsigned comment added by 88.8.79.148 (talk) 11:16, 15 July 2011 (UTC)[reply]
But the scammer is instructing the user to avoid doing the thing that the scammer wants him/her to do, because if the user types in the URL by hand, he/she will get to the real PayPal site. Unless of course the fake e-mail includes a forged link that has not only the actual URL, but the displayed text forged too, and the user happily types in the forged URL by hand. 194.100.223.164 (talk) 13:27, 15 July 2011 (UTC)[reply]
I used to get fake messages from 'Ebay' allegedly including a message from the customer that I failed to pay for some stuff I had never seen in my life, but I didn't get fooled. And I also got fake e-mails from Paypal, but I never had an account with them, so no bother there. For the bank bit, I specifically asked my customer care person the last time we talked that I don't want anything sent to me, be it e-mail or snail-mail, save for new debit cards if I request one. So when in doubt - doubt even more! --Ouro (blah blah) 11:31, 15 July 2011 (UTC)[reply]

Phone hacking[edit]

How do I keep my cell phone from being hacked? — Preceding unsigned comment added by 207.157.87.136 (talk) 20:25, 14 July 2011 (UTC)[reply]

See these articles: [1] and [2] -- Finlay McWalterTalk 20:39, 14 July 2011 (UTC)[reply]
Been in the UK, you don't have to be a celeb to get your phone hacked, apparently. I understand your worries. Quest09 (talk) 21:16, 14 July 2011 (UTC)[reply]
The news keeps talking about cell phone "hacking", but it isn't much in the way of hacking. Most phone message boxes require a 4-digit code to access the messages. You don't have an option to use more than 4 digits. If you don't set it, you get a default one, like 0000 or the last four digits of your phone number. So, a group of journalists call in and try the obvious choices: 0000, 1234, etc... They guess the 4-digit code and have full access to the phone messages. Never do they touch the actual cell phone. They don't have to see it, call it, or do anything to it. They are just calling the phone company's mailbox number, typing in the phone number for the mailbox they want to check, and guessing at the access number. Because there are only 10000 choices, it is rather easy to guess it by using brute force: get 10 people and have each one try 1000 possibilities. You'll get it in a couple days. -- kainaw 16:22, 15 July 2011 (UTC)[reply]

Computer memory[edit]

If a computer is restored to an earlier period in time, will the hard drive memory stay the same as it was in either that certain period time or the current that I was in? I'm going to be restoring a computer, and I just want to ahead of time since I've never restored a computer. SwisterTwister talk 22:22, 14 July 2011 (UTC)[reply]

I'm not entirely familiar with it, but according to System Restore and this MS support post it only affects system files and registry entries, while your personal files are unaffected (and, conversely, your personal files cannot be recovered by performing a restore in the event that you deleted them). I hope that helps - frankie (talk) 22:28, 14 July 2011 (UTC)[reply]
Still, it is always a good idea to make a backup of your files, just in case - frankie (talk) 22:31, 14 July 2011 (UTC)[reply]
Sorry, you need to be a little more specific about what exact operating system and additional software (if any) you are talking about. I suspect that Frankie is correct and that you are talking about the Windows Vista or Windows 7 System Restore, in which case Frankie is correct: all that gets affected is the system files and registry. The purpose of System Restore is that if you install some bad, nasty software that breaks your system somehow, you can use System Restore to "rewind" to before the install occurred, when your system worked. The files in places like the "Documents" folder won't be affected.
On the other hand, you may be referring to backup software like Norton Ghost, which can back up your hard disk to an image file that's a complete bit-for-bit image of the hard disk, and when you tell Ghost to "restore" the hard disk to an earlier date, it'll replace every single bit of the hard disk with the backup image file; so indeed your hard disk will look the same as it did the day it was backed up. Comet Tuttle (talk) 04:21, 15 July 2011 (UTC)[reply]