• LAN card of PC may be disabled- enable LAN card and check.
• PC Ethernet (LAN card) port fault/ Driver corrupt. Repair/Install new driver.
• Line problem between your end and DP / POP of Internet Service Provider (ISP). i.e. –cable
• switch / media convertor (device faulty)- check line.
• Spy ware is running on the computer and is interfering with the connection-Run antivirus and remove spywares.
• Third-party firewall software is blocking the connection-check whether soft firewall.
• Server down or due to higher network element faults at ISP-Contact with Customer Care Team.
• Error 651 is faced in windows 7 – error 851 is faced in windows vista-above.
• Error 815 may also occur due to restricted user (or we can say logged in with USERS other then administrator of the system).
• Error 815 may also occur due windows registry corruption

Error - Due to LAN port disabled or Lan card drivers not installed or lan card drivers not properly installed.
Solution- Enable the LAN port (or Local Area Connection). Or Installed the lan card drivers.

• Incorrect User name or password, or Spelling error.
• Due to forget of changed password.
• Due to authentication problem in AAA server of ISP.
• Error 691 due to wrong password.
• Error 629 in windows 7 due to MAC address authorization failure.

• Incorrect User name or password, or Spelling error.
• Due to forget of changed password.
• Due to authentication problem in AAA server of ISP.
• Error 691 due to wrong password.
• Error 629 in windows 7 due to MAC address authorization failure.

Due to corrupted Lan USB driver (If using). When USB to lan convertor NIC card is used.Install new dialer.

Due Registry Problem use scanreg command to repair dialer.

• TCP/IP may be corrupt, try re-installing TCP/IP.
• DHCP hand shake issue or ip release to client issue.

Due to the mismatch pppoe service installed – Remove all the pppoe service.

• Due to the browser issue-check on another browser.
• Due to the DNS failure issue-contact with customer care team whether specified DNS is working or not or check with the system whether it has obtained DNS or not.

• Viruses/spyware issue- check with the system whether antivirus is installed.
• Line connectivity issue- check with customer care team where issue is in line
• IBW issue-check with customer care team whether IBW constraint is there
• Subcriber plan-check with customer care team proper plan has been alloted.

• Check whether customer has subscribed static IP or not as by the default GTPL block SMTP port.
• Check proper configuration of outlook in case of static IP.

Switch/Media Issue.