Error 721 Remote Computer Is Not Responding
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I have FINALLY resolved an ongoing issue with our VPN connections that we have been experiencing for over a year now. I will share these findings with this forum in case others can benefit from our situation. error 721 the remote computer did not respond First let me explain the problem. The Problem: It can take up 6 retries for any error 721 vpn remote user to successfully created a remote PPTP connection to our servers. Whenever we try to connect it display the following message: Verifying error 721 vpn windows xp username and password... And it sit there displaying this message for about 30-40 seconds, then it says: "error: 721 The remote computer did not respond." Network Setup: We have two netopia routers on our network. They both have
Error 721 Directv
their own separate WAN connection (we use a lot of bandwidth, hence the need for two WAN connections). One RAS server is configured to use one router as it's gateway, and the other RAS server uses the second router as it's gateway. When PPTP connections are made, the connection comes in and back out the same router (this I made sure). We use a multi-NAT for routing service request to internal servers. FTP, WWW, RDP, PCAnywhere, SSL, PPTP, MAIL, etc...all these services are routed to internal servers/workstations. We have approximately 32 public IP addresses, hence why we use Multi-NAT for routing public services to internal servers. Everything works perfectly, EXCEPT PPTP (VPN) connections. We have struggled with this for a year now. For whatever reason, it struggles to make a successful connection to our RAS servers. Like I said, it can take up to 6 retries to successfully connect to our RAS servers (up to 30 retries if the remote user is behind a Linksys router). The Fix: Today, I decided to try something different. I decided to use the router's public IP address for PPTP requests, instead of one of the other public IP addresses our ISP assigned us, and simply forward PPTP (TCP 1723 & IP 47) requests to the internal servers. Therefore, the only difference is that I am using a pingable IP address which happens to belong to the router instead of using one of the public IP addresses I have NATed. For whatever reason, this solved our problem with connecting to the RAS server. We no longer have to retry up to 6 times to successfully connect. Conclusion: I have NO clue as to why I have to use the router's public IP address rather than any of the other 31 public IP addresses our ISP assigned to us. This was ONLY an
Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Server Fault Questions Tags Users Badges Unanswered Ask Question _ Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody http://www.pcreview.co.uk/threads/error-721-finally-resolved.1574450/ can answer The best answers are voted up and rise to the top VPN returning 721 error despite successful logins to/from other locations up vote 2 down vote favorite I am trying to connect a couple of Win XP desktops at a remote site, to the server (SBS 2008) of a central site, using a PPTP based VPN. When I try to connect, I http://serverfault.com/questions/110009/vpn-returning-721-error-despite-successful-logins-to-from-other-locations get the error "Disconnected. Error 721: The remote computer did not respond." Here is the strange part: The remote PCs can successfully dial out to another server using VPN. Similarly, I can successfully dial into the central site from my work PC. The remote computers are dialling out through a Netgear DG834Gv4 (latest firmware), and the server is behind a Draytek 2820. I have also tried using the Draytek as the VPN endpoint (instead of it doing pass-through), which again worked successfully from my work PC, but gave the same result from the remote site. I can ping the central site from the remote one, no problem. I can also telnet into port 1723 from the remote site. The central server is a domain controller with AD. At some point in the past, the remote PCs were successfully logged onto the domain, so now log into that (but obviously can't connect). The remote PCs are on a network which contains another SBS 2008 domain/domain controller/AD/server. However, the remote PCs are using the DG834 as their DNS/DHCP/etc. I and my colleagues are totally stumped - we know each end is fine indep
Protocol (PPTP) client. You may even get an error 721 after making an unsuccessful attempt to establish a dial-up connection after upgrading your computer to Microsoft Windows XP from earlier versions. The http://www.tech-faq.com/error-721.html exact error 721 description may vary from 'Remote PPP peer is not responding' to 'the remote computer is not responding'. Cause of Error 721 Point-to-Point Tunneling Protocol uses Generic Routing Encapsulation (GRE) for tunneled data and the error may occur if the network firewall does not permit the GRE protocol traffic. The Generic Routing Encapsulation protocol is used along with Point-to-Point Tunneling Protocol to create virtual private networks between the error 721 server and the client or between the clients. You may even encounter this error if the modem driver is not compatible with Windows XP. How to fix the Error 721 To resolve this error, you need to configure the network firewall so as to permit the GRE protocol 47. Also, you need to make sure that the firewall permits the TCP traffic on port 1723. Both of these conditions error 721 vpn are required in order to establish the virtual private network connectivity by using Point-to-Point Tunneling protocol. Installing the latest Windows XP compatible driver for the modem can also fix the problem in some situations. Follow Us! Rate this article: ★ ★ ★ ★ ★ Error 721, 0 / 5 (0 votes) You need to enable JavaScript to vote Mail this article Print this article Last updated 11 March, 2016. Related Posts How to Solve "Windows Installer Service Could not be Accessed" Windows Installer is a very important component of all Windows operating systems. It installs, uninstalls, ... 0xc0000135 Windows error 0xc0000135 is displayed when an application fails to initialize properly. It is also ... Compile Error in Hidden Module When starting up Microsoft Word or Excel (or other Office products), the "Compile Error in ... rejohn Long Path Tool help me a lot when i have an issue like file deleting or renaming the file. Also good to use if file name and file extension is too long. frederik "Long Path Tool" is very helpfull Search for: ReferenceSoftware Tutorials Unit Conversion Practice Tests Web Tools Site Index Audio-Video Databases Electronics File Compression File Conversion Gaming Graphics Hardware Internet IT Management Macintosh Microsoft Windows Mobile Devices Networking Pr