My computer shows that it is connected to LAN but I am not able to access the Internet,no one is able o access my compuer also.Please help me o overcome this problem.

Help me.

we need a little bit more information than that. What steps have you done to try and resolve this issue? Have you tried looking at your network connections? Is your WLAN enabled?

Run ipconfig /all from a command prompt
Click on Start then Run and paste the following into the Run box, exactly as show, including double quotes:

cmd /c "ipconfig /all > postme.txt & ping yahoo.com >> postme.txt & notepad postme.txt & del postme.txt"

and press ENTER.

A file will open in Notepad. Please copy and paste the contents here. Close the Notepad window and the file will be deleted and the Command Prompt window will also close.