Problem connection between laptop and pc via wifi. HELP

Let's start it fast okay?
I own a laptop and a desktop.
And, I wanted to share connection between them via wifi.
http://www.microsoft.com/windowsxp/using/networking/expert/bowman_02april08.mspx
This guide works on me.
But I encounter a problem while connecting to the host (My desktop)
It's like, you can't connect after you reset your connection or something, and it says "No Internet Access", and you can only connect just when your PC were freshly restart. IF you hand slipped and clicked the disconnect, you cannot connect just after you restart the PC again.
Steps repeated.

Anyone has idea about it?
Thank you

Please update your system specs. The link is in my signature.

Are all computers running Windows 7? Which computer has the internet connection? Did you install the operating systems yourself, or did they come preinstalled? Did you install the drivers, or did Windows install them automatically? Do those computers support Windows 7? Have you reviewed any Windows 7 ad-hoc guides, or just the XP guide that you found?

Thanks for replying, well I found it kinda weird.
Like, it currently can connect again after it were disconnect.
The WiFi hoster was my Desktop (XP), and WiFi client was my laptop (Windows 7)
Windows 7 comes with pre-installed.
I've checked my driver, and update the updates already.
Think I should try it for a few days more and find the solution.

Have you read any of the ad-hoc guides for Windows 7? Have you googled for "windows 7 adhoc"?

Thanks, I'll search for it now.

Help again, I accidently uninstall "Microsoft TCP/IP v6" on one of my network, and I can't find it to install again.
And this is the solution of this thread, but I don't manage to do it.
Ad Hoc Wireless Connection problem (I don't have Internet Access)
A little help here, so I would get rid of it.
Thanks.

Try to Download driver for your wifi connection for your laptop...