Wikipedia:Reference desk/Archives/Computing/2008 May 9

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[edit] May 9

[edit] Strange HDD problem

I'm trying to fix a problem for a friend who's hard disk mysteriously became password protected after a Windows crash. Worse than that, it's somehow set to the maximum security mode i.e you can't reset the password with a master password you need the user password (which obviously no one knows, since none was set). The good thing is the data isn't particularly important. In theory, the master password is unchanged (word 92 is 0xFFFE) so I should be able to use SECURITY ERASE PREPARE and SECURITY ERASE UNIT to erase and recover the disk without having to go through the rigamole of trying to convince Seagate that I/my friend didn't set a user password and it happened unexpectedly. But before I do that, I'm just wondering if anyone has any ideas I've missed. I've already tried mhdd to try various default passwords like "Seagate" +25 spaces but not surprisingly these don't work. I'm planning to try hddparm since I don't like the feedback I'm getting from mhdd, I'm not sure if it's working and I can't seem to work out how to do a full ID (I can with hddparm Windows but I'm having problems with that and there's no way I'm using it to erase so I'm getting a Linux recover CD). But that seems to be my last option. From what I can tell, it's difficult to recover via software only when security level is maximum, for example some expensive commercial utility (A-TT repair station 4.3) is unable to. And I've read that even attaching another controller board is pointless since the password data is stored somewhere on the HDD cylinder i.e. you need a special controller board which will ignore the password setting. Obviously anything like professional recovery companies, special tools etc are not under consideration since as I said, the data isn't important. Also, has anyone come across something like this before? I found this [1] and my friend said he came across one or two other people describing similar problems but it definitely seems a weird thing to happen. BTW, in case your wondering, I'm sure my friend is telling the truth and this really is how things happened. There is a slight possibility it's a virus but I haven't found anything like that and this happened in late March. N.B. I'm referring to a HDD ATA password as described at AT Attachment not a bios password or anything else. Nil Einne (talk) 00:05, 9 May 2008 (UTC)

[edit] Bypassing difference?

What is the difference between bypassing my cache brower and refreshing? What does it do differently? Basketball110 My story/Tell me yours 00:52, 9 May 2008 (UTC)

Refresh simply redraws the page. It doesn't necessarily mean that your web browser will fetch the source code and image data from the server again. Bypassing the cache will force the browser to re-fetch the source code and image data. So, assume you are looking at a page. The page is changed on the server. You hit refresh/reload and see the same page you were seeing before. That is because you just redrew the page you downloaded before the change was made on the server. Bypassing the cache will force your browser to download the new page and show that instead. -- kainaw™ 03:27, 9 May 2008 (UTC)


[edit] Geometry software

Hi. I am formatting a mathematical postulation, in the field of geometry. To help in my work, I need a method of constructing geometrical shapes down to an infinite point, and perfect circles (no constructed edges). Would the expertise present know anything about software that might help me? 3D modelling seen top-down (Gmax, Sketchup, etc) will not function because their circles are constructed by use of edges. Something akin to the .svg format might help, but I don't think any photoshop/paintshop program has much in the ways of helping geometrical shape construction. Perhaps a special plugin. Thanks in advance. Scaller (talk) 09:12, 9 May 2008 (UTC)

SVG leads to List of vector graphics editors and then Comparison of vector graphics editors. Find anything good there? --tcsetattr (talk / contribs) 11:09, 9 May 2008 (UTC)
That was a helpful list, and it turns out I have OpenOffice Draw! These (those I have so far read about or seen, a third) still do not perform the most important function of all, that of measuring angles. Scaller (talk) 12:54, 9 May 2008 (UTC)
The Geometer's Sketchpad has been bought! A marvelous piece of software, simple and with the desired functions. Question resolved. Scaller (talk) 19:21, 9 May 2008 (UTC)
You bought the software just so that you could use it? [It was just a silly joke. I understand that the distributor wants you to believe that you licensed it.] :) --Kushal (talk) 19:29, 9 May 2008 (UTC)

[edit] Getting electric shocks through iMac headphone jack

The iMac G5 I use at work has a bad tendency to emit electric currents through its headphone/line-out jack. While the stock iPod earbuds I usually use with it seem to insulate from this well enough, I get shocked something fierce when I try plugging in a pair of Sennheiser canalphones. Do the white Intel iMacs suffer from the same issue? (This doesn't seem to happen with the new aluminium iMacs; I plugged the Sennheisers into one of those and didn't get shocked at all.) --Lumina83 (talk) 10:36, 9 May 2008 (UTC)

...that, um, doesn't sound either safe or like it is working correctly? That definitely sounds non-standard to me. You might want to have that looked at. --98.217.8.46 (talk) 12:40, 9 May 2008 (UTC)

Does this Mac use a three-pin power connection? That is, does its power cord offer a Ground/Earthing pin? Does the mains outlet into which it is plugged properly connect that ground/earthing pin to actual ground/earth?
On the other hand, if the Mac connects with a two-pin power cord (so no ground/earthing pin), it's not that unusual for two-pin power connections to place some amount of leakage current on the chassis of electronic equipment, but if you can feel the leakage current, you should probably get it checked-out.
Atlant (talk) 12:51, 9 May 2008 (UTC)
I must congratulate Apple on the ultimate way to get people to buy their products (by administering electric shocks to anyone who buys another company's ear buds). Ivan Pavlov would be proud. :-) StuRat (talk) 14:48, 10 May 2008 (UTC)

[edit] CPAN for Java

Is there some central repository/directory of open source libraries for Java akin to Perl's CPAN (or even PHP's PEAR?) Or just good starting points for finding what's out there? Donald Hosek (talk) 17:22, 9 May 2008 (UTC)

There are some attempts to become the "CPAN of Java"; I find java-source.net in my bookmarks. Nothing that I'm aware of that is anywhere as authoritative as CPAN. For myself, I like google for finding Java code.notemployedbyorotherwiseassociatedwithgoogle Weregerbil (talk) 20:36, 9 May 2008 (UTC)
Weregerbil, you are a part of the brain drain too? Kushal (talk) 21:53, 9 May 2008 (UTC)

[edit] Removing Ubuntu

I installed Ubuntu a while ago on my Vista machine, and it worked like a dream, except for one problem: my inbedded wifi didn't work, so to get Internet on Ubuntu I had to sit in a totally different room from where I usually use the laptop using the ethernet cable. So, I have decided to remove it from my hard drive, because it is taking up too much space on my hard drive and I no longer use it. I have the Ubuntu Live CD, but have no idea how to uninstall it and get my partitions back to normal so I can use the 10GB I gave to it for my Windows PC. Can anyone help?--ChokinBako (talk) 20:24, 9 May 2008 (UTC)

You only need to delete the appropriate partitions and put them in a format that Windows can understand. Be careful which partitions you delete. You certainly do NOT want to delete /users partition unless you have your documents backed up. On second thought, would you want any help with making your internal wi-fi card work? Please let us know. Kushal (talk) 20:35, 9 May 2008 (UTC)
To be honest, I just want to free up the disk space. How is it possible to delete the partitions? I am actually originally a Mac user and am having trouble using stone-age hardware like this.--ChokinBako (talk) 21:08, 9 May 2008 (UTC)
Lets try this. Turn on the computer to go to windows. On your keyboard, press the [R] key while holding the Windows logo key. A dialog box should open up. Type in Diskmgmt.msc Click on OK. You should come up with something like this. Right click the partition you want to format and click format. [WARNING: Be very careful in this step! You do not want to delete something else by mistake.] Hope that helps. Come back if you need anything. Kushal (talk) 21:51, 9 May 2008 (UTC)
Documents would be the /home partition, not /usr .froth. (talk) 23:39, 9 May 2008 (UTC)
Thank you for the correction. Kushal (talk) 07:08, 10 May 2008 (UTC) about stone-age hardware, if I remember correctly, a recent edition of Consumer Reports rated Lenovo's ThinkPad T61 higher than a Mac in its category. I run a Mac and I love it but not all hardware that run Windows (oh, this includes Macs too) is bad. Kushal (talk) 07:15, 10 May 2008 (UTC)