These Steps worked for MTNL, BSNL, Verizon, AOL and other telecom companies which provide internet connection through a phone line.

Broadly Internet connection does’nt work due to two reasons
1. Your modem is not getting proper signals from the central office or Telephone Exchange.  (No Synchronisation)
2. Connection between your modem and computer is not fine. (No Route)

How to Recognise if there is a No sync or a No Route.
Thumb rule is if DSL or Link or Ready light on your modem is Solid green it means that your modem is in sync with central office and getting proper signals. If DSL or Link or Ready Light on your modem is blinking then its No Sync.

Troubleshooting guidlines for No Sync.
Restart the Modem before doing anything else.
1. Check if there is a Dial tone in the phone line….If not call your phone provider.
2. Check if your modem is connected properly to the phonejack via a phone cable….Try to    swap the ends of the phone cable.
3. Check the modem is connected directly to the phonejack without any filter or splitter thing.
4. There should be a filter on all the analog devices which are working on the same phone line ex. Fax machine, Answering Machine etc. except MODEM (Modem should not be connected via a filter.

TroubleShooting guidlines for No Route.
1. Restart the modem
2. check the physical connection between modem and computer. Ethernet or Data light should be green on your modem

3. Ipconfig -Click Start > Run > Type “cmd” and click OK
and in the black screen type “ipconfig” and hit enter key.

IP Address………..192.168.1.11
Subnet Mask……….255.255.255.0
Default Gateway……192.168.1.1

(if could’nt get these results check the ethernet adapter and try to reinstall the drivers for the ethernet card)

4. Configure Modem.
Open the GUI of the modem by typing the default gateway of the modem in the Address Bar of  IE or any other browser.
Put the Username and password provided by your ISP.

5. Ping google.com or any other website.

Click Start > Run > Type “cmd” and click OK
and try to “ping google.com”
If google is pinging you are good to go online.
If google is not pinging then try to ping google by its IP Address

6. ping 74.125.67.100
if google is pinging by the IP address and not by google.com
then go to Run> type “services.msc”> and click ok
and restart “DHCP Client” and “DNS Client”

7. Check TCP\IP Settings

“Lan connection > Properties > Internet Protocol (TCP/IP)”  and click on “Obtain an IP Adresss automatically”.

8. Reset Socket files….God Command to fix your internet connection!
Click Start > Run > Type “cmd” and click OK
and type “Netsh Winsock Reset Catalog”

and then restart the computer. (This command runs only on windows XP SP2 or Higher Versions)

9. Disable any firewall or any other Antivirus……Happy Browsing.