Its often been the case that you cant connect to the internet because some corruption has damaged your winsock set up, most folks end up reloading their operating system to fix this annoying episode but with these two simple files you can be back online in a reboot.
http://www.cexx.org/lspfix.htmLSP-Fix is a free Windows utility to repair a loss of Internet access associated with certain types of software. This type of software, known as a Layered Service Provider or LSP, typically handles low-level Internet-related tasks, and data is passed through a chain of these programs on its way to and from the Internet. However, due to bugs in the LSP software or deletion of the software, this chain can get broken, causing the Internet connection to become inaccessible.
http://www.snapfiles.com/get/winsockxpfix.htmlWinSock XP Fix offers a last resort if your Internet connectivity has been corrupted due to invalid or removed registry entries. It can often cure the problem of lost connections after the removal of Adware components or improper uninstall of firewall applications or other tools that modify the XP network and Winsock settings. If you encounter connection problems after removing network related software, Adware or after registry clean-up; and all other ways fail, then give WinSock XP Fix a try.
Both are spyware/ad free and have proved themselves very helpful when I have encountered connectivity problems.