There are many reasons why you cannot access the internet.
1. The computer is not connected to the network because it cannot get the right ip address from the router.
--- This happens when your computer cannot communicate properly to the router and get the ip address from the DHCP server. Notice that the status of your LAN has a Exclamation Mark.
2. It is infected by virus which disables internet access.
--- The best thing is to disable your network connection first and remove th virus or spyware using COMBOFIX. BEst results can ba achieved by running it in safe mode. Afterwards install a new antivirus software.
3. A Firewall software locked internet connection.
--- some antivirus software contains a functionality whick locks network access in orer to prevent intrusion.
4. Winsock error.
--- In many cases, your computer is connected to your network but still, you cannot access the internet. In order to solve this problem, try these steps.
4a. click Start Menu then run
4b. type "cmd" then press enter
4c. type ipconfig press enter. it will display the following
Windows IP Configuration
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 192.168.0.xx
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.0.101
4d. locate ont he result the Default gateway. then type "ping gateway ip address" (example: ping 192.168.0.101 )then press enter. It will display the following.
C:\Documents and Settings\Administrator>ping 192.168.0.101
Pinging 192.168.0.101 with 32 bytes of data:
Reply from 192.168.0.101: bytes=32 time<1ms TTL=150
Reply from 192.168.0.101: bytes=32 time<1ms TTL=150
Reply from 192.168.0.101: bytes=32 time<1ms TTL=150
Reply from 192.168.0.101: bytes=32 time<1ms TTL=150
Ping statistics for 192.168.0.101:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
Reply means you were successfuly connected to your router. If it displayed Request Timed out, check first your local connection.
4e. Next is test the connection to the internet. type ping www.yahoo.com press enter. If it displayed Reply, your only problem is browsing. You computer's winsock needs repair.
"In computing, the Windows Sockets API, which was later shortened to Winsock, is a technical specification that defines how Windows network software should access network services, especially TCP/IP. It defines a standard interface between a Windows TCP/IP client application (such as an FTP client or a web browser) and the underlying TCP/IP protocol stack. The nomenclature is based on the Berkeley sockets API model used in BSD for communications between programs. Initially, all the participating developers resisted the shortening of the name to Winsock for a long time, since there was much confusion among users between the API and the DLL library file (winsock.dll) which only exposed the common WSA interfaces to applications above it. Users would commonly believe that only making sure the DLL file was present on a system would provide full TCP/IP protocol support.
Winsock Repair Tool for Windows XP
WinSock 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. It can create a registry backup of your current settings, so it is fairly safe to use. We actually tested it on a test machine that was having a Winsock problem due to some Adware removal, and after running the utility and rebooting, the connectivity was restored.
Download the file here:
http://www.snapfiles.com/downloads/winsockxpfix/dlwinsockxpfix.html
http://support.microsoft.com/?kbid=811259
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