Error 721

“Error 721: The remote computer is not responding.”

“Error 721: Remote PPP peer is not responding.”

Do these errors sound familiar? You may be getting error 721 messages for a variety of reasons including an incompatibility problem after upgrading to Windows XP, trying to connect to a Virtual Private Network through a Windows Server based remote access server, or by simply trying to connect to an internet service provider. The exact text of the messages may vary slightly.

Below, we’ll take a look at the different scenarios for Error 721 and give you advice for solving your problems.

Internet Service Provider Error 721:

The “Remote PPP peer is not responding” error is typical of a problem related to a dial-up networking connection to an internet service provider. The problem could lie in the way the connection is set up or there could be a technical problem on the ISP’s end. To work through this problem try the following steps:

·          Try connecting using a different dial-up access number if available. Sometimes a technical problem with a particular access number is the culprit

·          Double-check your dial-up networking connection to make sure it is set up correctly. If a recent area code has been changed, you may need to make minor adjustments.

·          Double-check your encryption settings. Different providers may have special encryption settings that you need to accommodate by adjusting these settings. For example, NetZero requires that the advanced settings found under the Security section of their network connection is marked for an Unencrypted Password (PAP). Check with your ISP for their requirements.

 Recently Upgraded PCs:

If you have just upgraded to Windows XP, you may get error 721 messages when you try to establish a dial-up networking connection. This particular issue is related to incompatibilities with Lucent Win modems that were provided with numerous HP Pavilion computers. If you have an HP Pavilion computer and recently upgraded to Windows XP, contact HP for the latest compatible drivers for the modem.

Failed VPN connections:

The following advice applies to:

·          Microsoft Windows 2000 Advanced Server

·          Microsoft Windows 2000 Server

·          Microsoft Windows NT Server 4.0 Standard Edition

·          Microsoft Windows Server 2003, Enterprise Edition (32-bit x86)

·          Microsoft Windows Server 2003, Standard Edition (32-bit x86)

·          Microsoft Windows Small Business Server 2003 Premium Edition

·          Microsoft Windows Small Business Server 2003 Standard Edition

If you get your error 721 message after trying to establish a Virtual Private Network connection through a Windows Server-based remote access server using a Point-to-Point Tunneling Protocol client, the connection has failed. You may also see the following event logged in the server’s System log if you are using a Windows NT Server 4.0 based remote access server:

“Event ID: 20073  Source: Router  Type: Error  Description: The following error occurred in the Point to Point Protocol module on port <Port Name>: The PPTP negotiation is not converging.”

This error 721 can happen if the network firewall prohibits Generic Routing Encapsulation protocol traffic. Generic Routing Encapsulation is IP Protocol 47. PPTP uses Generic Routing Encapsulation for tunneled data.

To solve this problem, reconfigure your network firewall to allow Generic Routing Encapsulation protocol 47. In addition, make sure the network firewall also allows TCP traffic on port 1723. If you wish to establish VPN connections with PPTP, both of these conditions must be enabled otherwise you will continue to get error 721 messages.

Depending on the type of error 721 you get and the circumstances surrounding it, you should be able to fix the problem by doing the appropriate recommended fixes.