This article: http://docs.info.apple.com/article.html?artnum=305716 has some good tips.
This article also will likely resolve the issue:
Make sure you're running Service Pack 2 on WinXP
(Right click on My Computer from your Start menu, and click Properties)
It's also helpful to connect the device directly to a usb on the rear of your pc tower (no hubs or extension cables).
Also, go into Control Panel -- Add/Remove Programs
Make sure Apple Mobile Device Support is installed
If you don't see it listed, reinstall iTunes
thanks again to casper gemini...
my vaio runs on winxp sp2 and tried to connect iphone directly to the usb ports as well. basically i checked everything you listed and there must be something magical missing still. there must be. i have a strong faith in both my vaio and iphone. but......help.....
vaio sz110 Windows XP
ok.. i tried and tried. finally something is responding. the HARWARE UPDATE WIZARD showed up and ask to install the driver for iphone. i choose to install the software automatically and it responded me " hardware was not installed because the wizard cannot find the necessary software.
what should i do now? anybody knows?
Sorry you're having problems. If you have not done it yet, try uninstalling iTunes and reinstalling. You can download a standalone iTunes installer from http://www.apple.com/itunes/download/. That should have an uninstall option in the installer. Post back if that does not work.
have you tried the obvious... So obvious that its one of those things that's really easy to overlook - Check your cable!
I had the same issue, and then switched to my wife's iPhone cable and, it started working immediatly!
Really frustrating cause my cable worked fine for the first hour or two.
maybe a regular iPod cable will work for you.
thanks everyone who have tried to helped me so far.
i got my phone activated through my office computer(a pc) successfully. still, my laptop just couldn't detect the iphone. tried to reinstall itune, swap cables, update xp service pack 2. the system still ask me for the driver. it's so weird. the only things that i can think of would be to format my computer or get a macbook. what should i do?
O yea, also I forgot to tell you to try this.
Since it's a laptop, the Power of the USB ports may be too weak.
You can try buying a powered USB 2.0 Hub for like 30 buks, Belkin I reccommend, that plugs into the wall.
You can get a PCMCIA adapter for the laptop, that has a power jack also, but the power jack comes with a small usb power cord that draws additional power from a USB port in addiction to the power from the PCMCIA card.
It could be that the port isn't supplying enough power.