Wikipedia:Reference desk/Archives/Computing/2009 March 18

= March 18 =

C#.. how to show a tooltip anywhere on my screen?
I'm developing a C# application, and i need to show a tooltip to the user at the cursor's position. wherever the cursor is, even outside the form of my application. PS:I pay alot of attetion to the performance. any idea? Thanks in advance Supersonic8 (talk) 00:21, 18 March 2009 (UTC)


 * Put a ToolTip control on your form/whatever control you want. When you call  (or whatever it's called) it shows the tooltip relative to the control's location. Take a look at the   function on every control. What you want to do is to convert a screen point into a point relative to the control's location. --wj32 t/c 07:44, 18 March 2009 (UTC)


 * I don't want to show this tooltip to a specified control, i just want to show it at the cursor's position.. it's like a dictionary application; when the user stops at a word on his screen, a tooltip shows with the word's translation. thanks Wj Supersonic8 (talk) 12:03, 18 March 2009 (UTC)


 * This doesn't force you to show the tooltip on the control. You have to use the control as a reference point because the ToolTip control uses it. --wj32 t/c 04:56, 19 March 2009 (UTC)

Effect on humans
What is the effect on humans when they work continiously with out a break on a computer for 180days? —Preceding unsigned comment added by 220.227.88.91 (talk) 01:52, 18 March 2009 (UTC)


 * Well the worst effect will be sleep deprivation, if you really mean "without a break". (Assuming, of course, they are allowed to eat and drink fluids.) --98.217.14.211 (talk) 02:45, 18 March 2009 (UTC)
 * Lee Seung Seop. - Akamad (talk) 02:46, 18 March 2009 (UTC)


 * Forget 180 days, try 49 hours. ←  Spidern  →  16:05, 20 March 2009 (UTC)

Problem with software requiring Adobe Reader
I am working with a PC running Windows XP. It is my family's computer. They aren't so good with computers and as I am home for a few days, I am douing some general software maintenance for them. I do certain things out of principle (mostly) such as using Firefox instead of IE and using Foxit Reader instead of Adobe Reader for pdf files. My brother received some proprietary software from his school on CD which I installed for him. This software is reference software. It seems to simply organize a bunch of pdf files. When it is run it calls on Adobe Reader to view these files. So, now that I have uninstalled Adobe, my brother's software does not function (at all). The desktop shortcut it installed calls an ini file. I am pasting the ini file contents below just in case they may be useful (If you are sure it isn't helpful and is just wasting space, feel free to remove it and this reference to it). Is there a way to make this software use Foxit instead?

Chrissekely (talk) 04:32, 18 March 2009 (UTC)Chris


 * I doubt it. It sounds like it was made using the proprietary Acrobat control/API and doesn't have the flexibility to substitute with another (which may or may not exist anyway). To put it more plainly, it is looking for a file (one that helps it run PDFs) that calls an instance of Adobe Reader, and it has certain expectations of what that file will look like and how it will operate. Web browsers are often flexible in letting you determine which files it calls, but other programs are usually not. --98.217.14.211 (talk) 12:43, 18 March 2009 (UTC)


 * When you uninstalled Adobe Reader, did the uninstall leave .PDF files associated with the deleted Adobe program? One way to test, is find a different .PDF, double-click on it - if .PDF files are still associated with Adobe, it should attempt to start it and fail.  Try reinstalling your Foxit Reader and see if it associates .PDF files with Foxit.
 * One thing though, why mess up your family's computer just because you don't like Adobe Reader "out of principle"? It seems very high-handed of you to make that judgement for everyone else.  Install Foxit for you to use when you are at home, but what is the harm in leaving Adobe installed for your less savvy family to use?  Astronaut (talk) 03:40, 19 March 2009 (UTC)

Thank you guys for your help. I did, unfortunately, have to install Adobe after all. I was hoping that maybe there would be some sort of registry fix, or the like, that would allow Foxit to "pretend" to be Adobe. If that makes any sense at all. Now, I'm not being high-handed or messing up my family's computer. Far from it. I'm nearing the end of the long process of backing up files, formatting the hard drive, and reinstalling everything they need. They have a relatively slow computer, though, so I was trying to keep things slimmed down, quick and efficient. As many people feel that Adobe Reader is bloat-ware, it didn't seem to be an optimum choice. Chrissekely (talk) 05:15, 19 March 2009 (UTC)

wii mod chip
is a wii mod chip required to play downloaded games on the wii system —Preceding unsigned comment added by 97.116.45.221 (talk) 04:18, 18 March 2009 (UTC)


 * If you mean "Pirated" games, then yes, I believe that you will require a mod chip.
 * If you mean "Homebrew" games, then no, that can be achieved, with some difficulty, by exploiting a glitch in Twilight Princess.
 * If you mean "WiiWare" games that you pay money for, then no, your console can play those out of the box. APL (talk) 13:03, 18 March 2009 (UTC)


 * Be aware that I've seen a warning on many of the newer games available in the shops. I can't remember exactly waht it says, but gist of it is that the game might not play on modded consoles.  I strongly suspect that modding the console is not reversible and therefore might permanently mess up your future ability to play genuine, purchased games.  Astronaut (talk) 03:45, 19 March 2009 (UTC)


 * While modding involving soldering is unlikely to be truly reversable, many are firmware updateble I believe and I presume it's possibly to remove the mod chip if you really need to. Nil Einne (talk) 12:33, 23 March 2009 (UTC)

Lahey compiler (FORTRAN programming)
i am using Lahey 95 compiler,i have run some programmes with this, my one programme is not running. after compiling it tells some warnings but zero errors ( it was running some programmes with warnings earlier) and it is nor creating .exe file, is it creating it somewhere else, can anyone suggest what should i do? —Preceding unsigned comment added by 203.199.205.25 (talk) 05:45, 18 March 2009 (UTC)


 * I suggest fixing the conditions which cause the warnings. I've had the problem before that only a certain number of messages are reported, and, if you have too many warnings, the errors at the end get truncated from the error report. StuRat (talk) 15:13, 18 March 2009 (UTC)


 * "Too many warnings" can be an error condition. (It is also possible to have a compiler handle warnings fatally with a configuration flag.) Generally, you should either fix the warnings or tell the compiler to disregard (useless) warnings. If the compiler fails to generate an executable with zero warnings and zero errors then something is seriously wrong. –  7 4   21:15, 18 March 2009 (UTC)


 * That's right, there can be a compiler setting to abort compilation if it gets over a certain number of warnings. StuRat (talk) 19:12, 19 March 2009 (UTC)

Databases
How can I test the efficiency of databases in Microsoft Access and the effectiveness of the database and database reports? --124.254.77.148 (talk) 05:51, 18 March 2009 (UTC)


 * Testing the efficiency of a database is tricky, as there are many different types of efficiencies to measure. For example, there is the lookup speed in a sorted table using the primary key, the lookup speed in an unsorted table using a partial (non-key) character string, the speed to add a record to the end of a table, the speed to insert a record in the middle of a table, the speed to sort a table, the speed to do a table join using unsorted records in both table, the speed to delete a record, etc.  You would do best to develop a list of standard tests, and a large amount of standard test data, then try this out on the database systems in question, timing the responses.  This is not a quick process, as loading the test data alone can take hours.  The closer the test is to your normal business processes, the more useful it will be, for you.


 * You could also rely on standard tests performed by others, but those won't be specific to the type of things you do, the type of hardware you have available, etc. StuRat (talk) 15:10, 18 March 2009 (UTC)

Lookup table Excel
I want create a structure in MS Excel that allows me to select a value from a table by "addressing" it with the value from a specific cell, just like a lookup table or, in other words, if I was dealing with a database, the SQL query I'd use would be like "SELECT x FROM y WHERE k = m", where "m" would be the value of the mentioned cell that changes dinamically according to some variables, "x" would be the column of the table "y" containing the value I want and "k" would be the value I want to test. Is that possible? —Preceding unsigned comment added by 213.13.148.4 (talk) 09:26, 18 March 2009 (UTC)
 * Have you tried using the 'if' command? Googlepeek here.  Lanfear's Bane |  t  09:35, 18 March 2009 (UTC)
 * The IF function only allows 10 nestings, however, a few more combinations exist, that's the source of the problem. Along with that, even if I could nest the number of IFs I wanted, it would result in a excessively long formula. 213.13.148.4 (talk) 10:09, 18 March 2009 (UTC)


 * VLOOKUP/HLOOKUP ? Gandalf61 (talk) 10:33, 18 March 2009 (UTC)
 * I think that's the function I needed. Thanks a lot! 213.13.148.4 (talk) 10:53, 18 March 2009 (UTC)


 * Sounds like you have Excel and know some SQL. Have you tried this?  I have not (so this is not an endorsement), but it looks like it might be useful, and it says it's truly freeware.  --Scray (talk) 03:57, 19 March 2009 (UTC)

computer - DVI-D and VGA
I installed both the VDI-D and the VGA at the same time. My hard drive won't run. Is that why and how can I fix it?204.65.61.203 (talk) 12:44, 18 March 2009 (UTC)


 * Are you saying you had the computer case open and were installing graphics cards ? If so, I suppose a spark of static electricity could have fried the circuit board on the hard drive, but this type of thing is quite rare. StuRat (talk) 15:01, 18 March 2009 (UTC)

Bluetooth and cell phone interraction
Is is possible that my bluetooth is draining the battery on my cell phone? Both bluetooth and LG said no, but I've noticed evidence to the contrary. Then last night, I laid my fully charged phone next to my bluetooth which was off and the phone was drained this morning.Beach999 (talk) 14:23, 18 March 2009 (UTC)


 * IMHO, bluetooth is a huge drain on my phone's battery - I leave it switched off except for short periods when I actually need to use it. Same goes for the phone's MP3 player and the 3G network service.  Leaving all that stuff on, drains my phone's battery in no time.  Astronaut (talk) 03:28, 19 March 2009 (UTC)

How to enable net send
Moved from Miscellaneous desk

how to enable net send service in a network?

when i try to send any message to any pc in the network, it says " An error occurred while sending a message to (PC NAME). The message alias could not be found on the network. More help is available by typing NET HELPMSG 2273."

when i try the help msg: net helpmsg 2273 the following message is displayed: "The message alias could not be found on the network.

EXPLANATION This message alias could not be located.

ACTION: Check the spelling of the message alias. If it is correct, then the computer that is to receive your message may be busy. Try sending the message again later."

when i try the help msg: net helpmsg 3777 "Sending files is no longer supported." message is displayed please provide a solution. —Preceding unsigned comment added by Nag183raj (talk • contribs) 10:01, 18 March 2009 (UTC)


 * Would this not be better on the computing helpdesk? I would move it myself, but not yet learnt how to do that sorry... Gazhiley (talk) 11:01, 18 March 2009 (UTC)


 * WP has an article, Messenger service, which may be of some use. Before you can use net send, you need to start the messenger service.  In XP, you can do this by going to the control panel, choosing "Administrative Tools" and then "Services".  Find Messenger in the list, right click and click properties, and then you should be able to enable the service.  I think you will have to do this individually on each computer.  However, this functionality has been used for malicious purposes (hence it is disabled by default), so you probably shouldn't enable it unless it is really necessary. 81.98.38.48 (talk) 17:03, 18 March 2009 (UTC)


 * This sounds like a DNS issue. If this is on a home network (or one without a DNS server), this may be difficult to fix reliably (at least in the dynamic sense). To determine if this is the case, try using the "net send" command using the IP of the remote computer rather than its name. If this works, let us know and I can tell you where to go from there. The next step would be to edit your "hosts" file to enter a name and static IP. aszymanik   speak!  06:06, 24 March 2009 (UTC)

SATA power supply
I am going to add a SATA hard disk to my computer. The only spare power supply connectors I have are a Berg (floppy drive), a 6-pin aux (whatever that is for) and a P4. Would it be possible to use any of these to power a SATA device? If so, does anyone know where I could find an adapter? If this is not possible, I know there are some adapters around to split a Molex connector into two. What constraints are there on this working? Is it just the total power rating of the PSU I need to worry about? 81.98.38.48 (talk) 17:34, 18 March 2009 (UTC)


 * Yes, the molex->SATA thing is the way to go. Some PSUs are "single rail", meaning that all the devices are on the same circuit, and the total power used is just totalled up vs the power rating of the PSU. Some (generally larger, fancier PSUs) are "split rail" or "dual rail", where there are two (or sometimes three) separate power sections (and each bunch of devices uses up its portion of the total).  There should be a sticker on the side of such a PSU, detailing which connectors are on which rail and what the distribution of power is (I think generally the CPU/motherboard/system-fan is on one, peripherals like disks on the other). If you're really worried, connect a multimeter up to an unused molex when the system is operating - if all is well you should see the various pins floating at or slightly above the specified voltages (and if things are overloaded they'll dip down when demand is high). 87.112.22.179 (talk) 17:57, 18 March 2009 (UTC)


 * OK, I'll try this. Thanks a lot for your help! 81.98.38.48 (talk) 18:11, 18 March 2009 (UTC)

Switching to Linux - some questions before I do
I'm thinking of replacing WinMe on an old computer by Linux. But I'm wondering about maintaining it and the underlying system. Does Linux have a system for installing hardware driver updates? What about Linux updates and fixes? Is it possible to flash the BIOS in Linux? What is the most popular version of Linux (and hence the one with the greatest technical support, most debugged, etc)? Thanks 78.145.16.118 (talk) 22:02, 18 March 2009 (UTC)


 * Hardware driver updates: yes, it'll do so itself, almost entirely automatically. No more going to the manufacturer's website to download some executable thing.
 * Updates and fixes: ditto. Almost all the applications (and thus fixes) people run come via the distribution (see most popular, below), so you get stuff all from the same source (like windows update, except for everything on the system).
 * Bios updates: sometimes, but you only need to do that if something is broken, so it's really very rarely necessary.
 * Most popular: Ubuntu linux, Fedora linux - although they may be rather too heavyweight to run on a WinME era machine, so Xbuntu or Puppy Linux might be better.
 * -- 87.114.148.185 (talk) 22:10, 18 March 2009 (UTC)


 * On thinking further, I think Puppy Linux is the best option (of those listed above; other people may recommend alternative light-weight Linuxes). Puppy is easier to boot from a floppy disk, and a PC from the WinME era may not be able to boot from a CD, which is something the larger Linux distributions will mostly expect. 87.114.148.185 (talk) 22:19, 18 March 2009 (UTC)


 * I believe that almost all Win ME PC's will be able to boot from a CD. --Andreas Rejbrand (talk) 22:37, 18 March 2009 (UTC)

Thanks. My WinMe computer is not so primitive as I think you imagine. It has a 566MHz CPU, 512MB memory, a CD drive than can be booted from, etc. Something important I forgot to ask - will I be able to continue to use my reliable HP Deskjet 930c printer please? Which reminds me - it runs via USB. Will USB attachments like still-cameras and pendrives still work?78.145.16.118 (talk) 23:19, 18 March 2009 (UTC)


 * Printer: "perfectly" (don't be put off by that page; a modern linux will find and install software for the printer without you setting much of anything)
 * still cameras and pen drives: perfectly.
 * 87.114.148.185 (talk) 23:28, 18 March 2009 (UTC)


 * I use HP printers via USB - they all seem to work very well. Mine has a scanner and a fax - and those work perfectly too.  I agree - pretty much any USB device that adheres to USB standards - eg "mass storage", "printer" or "human interface" device will work just fine - so cameras, mice, keyboards, joysticks, thumb-drives - all work OK.  However, some more obscure USB devices that expect to have their onboard software downloaded to them via some kind of Windows application may not work...or may require more messing around that you could possibly stomach!  Good luck - and don't hesitate to ask more questions here - the ratio of Linux experts to Linux questions is ridiculously high here! SteveBaker (talk) 02:33, 19 March 2009 (UTC)


 * I've setup my old PC (which used to have just WinMe) to be a multiple boot system - WinMe plus a whole load of small linuxes on separate partitions. It works pretty well for basic web surfing and as a test bed for the linuxes.  It also works well with my printer.  Astronaut (talk) 03:24, 19 March 2009 (UTC)

Thanks. Are there the Linux equivalents of free anti-virus and spyware scanners and protection please? And the most difficult thing I would have to do is install an ethernet card, then set up my (external) broadband modem even though the ISP only spports Windows. I dont know anything about the technicalities. 78.146.26.220 (talk) 11:47, 19 March 2009 (UTC)


 * Malware: There are, in practice, no viruses or spyware that will run in Linux (in theory these might exist at some point in the future, and again in theory a few examples have been created in the lab, but none are in the wild and you could't be infected with one even if you were to try). Consequently there is absolutely no need whatever for an anti-virus or anti-spyware solution for a linux desktop or laptop machine. There are antivirus programs for Linux (such as Clam AntiVirus) but these are intended to be used on server machine (such as a company's email server) where there is a need to block viruses before it gets to a windows machine. So, in summary, you're all set.
 * Ethernet: any PCI ethernet card you install should just work with no effort or configuration on your part.
 * Broadband: As you have an external broadband box, as long as you're using ethernet (and not USB) to talk to it then it'll just work. USB broadband connectors often will work, but they're generally a bad idea (for Windows users every bit as much as Linux ones), and it seems you don't have one of those anyway.
 * 87.112.92.44 (talk) 12:57, 19 March 2009 (UTC)
 * I wouldn't worry about your ISP only supporting Windows. ISPs don't (can't?) do something to the connection to prevent non-windows computers using it.  It will only ever become a problem if you call them with a technical support query; such as how to set up their service for use on your PC - ie. the instructions will be for Windows PCs only.  As 87.112... mentions above, it should all work with no additional setup from what you are currently using.  Astronaut (talk) 14:37, 19 March 2009 (UTC)


 * To "Activate" a Comcast account you'll need a windows computer. I spent hours on tech support trying to figure this out. Tech support was unhelpful. ("Linux? Oh. Ok then, I can mail you a CD with Internet Explorer on it." )  APL (talk) 16:00, 19 March 2009 (UTC)

Help! Excessive hard drive activity
You were so helpful last time, I thought I'd give you another shot: For the last few days my computer (Windows XP) has suddenly slowed to a halt with the hard drive LED on solid around mid-evening and continues like this for the rest of the evening even after restarts and being left off for half an hour or so, it will then work again the next day. I noticed this time that it was at almost exactly 8pm, which suggested some kind of scheduled scan going wrong. I eventually managed to get Task Manager to load and CPU usage was minimal, I got it to show the various I/O columns and the only processes showing continuous I/O activity were lsass.exe (part of the OS, I believe, so I left it alone) and vsmon.exe (part of ZoneAlarm). So I've gone into safe mode (which works fine) and set ZoneAlarm as well as AVG and SpyBot (the two things likely to do scheduled scans) not to load at startup, but the problem hasn't gone away. It seems very unlikely that it is due to paging since it is happening with virtually nothing running - Task Manager didn't show any massive memory usages, either. There seems to be some issue with network connectivity when it all starts to go wrong - at least, Skype gets disconnected and tries (sometimes successfully) to reconnect. Any ideas? --Tango (talk) 22:35, 18 March 2009 (UTC)


 * If memory serves, your previous problem amounted to "massive disk errors resulting in very bad performance". Your current problem seems like "massive disk activity resulting in very bad performance". I guess you've checked the error logs as last time, but this time there aren't lots of errors?  Anyway, I think you've killed the low hanging fruit the last time (and again this time) - it's my experience that a problem that persists past the obvious virus/update/remove-junk/no-reported-errors phase is probably not worth chasing. If I were in your position, I'd likely feel that the blinking thing had wasted too much of my time, and risked too much of my precious data, and I'd now be backing up in preparation for a restore-to-factory-settings. That's really the only way to definitively reject the hypothesis that the problem isn't infact a failing disk. 87.114.148.185 (talk) 22:57, 18 March 2009 (UTC)
 * I hadn't thought to check the error logs (duh!), when I did I found some errors relating the Automatic Updates. Turning off automatic updates seems to have fixed the problem. The annoying thing is that it shouldn't have been on in the first place (I have it set to download automatically and then ask me about installing them), but that had been changed to the default "let microsoft break my computer whenever they like" setting - I suspect my university is responsible, via the program that make us run to verify we have up-to-date antivirus software, etc. Had I known it was installing updates automatically I might have worked out what the problem was (my guess that it was some kind of scheduled activity going wrong was correct, I just didn't think to check a scheduled activity I had explicitly turned off!). I will be making an official complain in the morning... --Tango (talk) 23:25, 18 March 2009 (UTC)
 * Such a complaint is unlikely to be worth registering. Many universities enforce automatic updates, but to mitigate impact they have an internal approval process - they don't accept all updates from Microsoft automatically.  This allows critical (security-related) fixes to be applied rapidly, reducing the risk of compromised machines on the network.  --Scray (talk) 03:51, 19 March 2009 (UTC)
 * Yeah, after my initial anger subsided I came to the same conclusion! This is my private computer, all they did is change my settings to download updates from Microsoft automatically. It's not that they did that that really annoys me, it's that they didn't tell me there were doing it (the program they make you download is supposed to just check you have a virus scanner, etc., it doesn't say anything about changing stuff). Had I known they had done it, I would have thought to check if that was the source of the problems much earlier. --Tango (talk) 14:06, 19 March 2009 (UTC)

Any way to tunnel traffic from behind a GET-only (no CONNECT) HTTP proxy?
Is there any way to tunnel traffic through a HTTP proxy server that does not allow CONNECT, only GET, POST, etc.

I have no direct access to the internet, and the only access is provided through this proxy.

Looking to tunnel SSH, which I could then use to tunnel other traffic.

Thanks. —Preceding unsigned comment added by Charlieham (talk • contribs) 23:52, 18 March 2009 (UTC)


 * Do they allow SSL/TLS on 443? If not, you are more or less SOL since GET/POST is all you have.  I have never heard of a tunnel tool that can make use of that but there may be one out there.  --Jmeden2000 (talk) 13:48, 20 March 2009 (UTC)

Discrete Hard Drive Speeds
I can't seem to see a reason why hard drive speeds seems to vary in discrete steps e.g. 4200, 5400, 7200, 10000 or 15000rpm. While I imagine it relates to the interface speeds I can't see the details anywhere why speeds in-between these are not seen. --Trieste (talk) 23:56, 18 March 2009 (UTC)


 * It's not the interface speeds, it's market segmentation (that is, it's a deliberate set of speeds chosen by the hard drive companies' product marketing departments). Hardware wise they could choose other speeds (and in practice a given drive doesn't necessarily spin at exactly that speed; they're probably a touch faster). An additional reason is the design of the decoding chip (that processes pulses that come of the read/write heads) - this has to be designed to very (very) high tolerances, and if drives had more variety of speeds they'd have to have a bigger selection of decoder chips, which means more work and more testing . If a given manufacturer only makes drives of three speeds, they only need to have three such decoder chip designs on the go at any time, and an improvement to the design of one (or a cost optimisation) means that benefits all their drives which contain that chip. To keep costs down (it's a really price-aggressive market) even the biggest players only make a handful of different drive designs at any one time (each design having the same board and technology, but with varying platter and sometimes head characteristics). Dog Day Today (talk) 00:23, 19 March 2009 (UTC)


 * Also, the slower drives (4200, 5400) are usually reserved for notebooks Nchalada (talk) 10:36, 24 March 2009 (UTC)