[Okta Webinar] Learn how to a build a cloud-first strategyRegister Now

x
?
Solved

PPTP VPN not accepting connections

Posted on 2008-11-12
9
Medium Priority
?
1,215 Views
Last Modified: 2012-05-05
I have a SBS server at one of my customers that rebooted last night to finish some security updates. Now the RRAS VPN will not work. Nothing has changed with the firewall.

When we try to connect we get either error 800 or error 678.

I ran portqry.exe from the box itself and it tells me that 1723 is NOT LISTENING. I don't see how this is possible. RRAS is running and there are no errors in the event logs. I'm looking at the RRAS MMC snap-in and the server is up. I have disabled and recreated the RRAS VPN a few times now using both the SBS wizard and from the MMC snap-in.

All other common ports seem to be fine such as 25, 389, 445, 3389 etc.
0
Comment
Question by:jhalscott
  • 5
  • 2
  • 2
9 Comments
 
LVL 3

Expert Comment

by:sukumade
ID: 22941060
I wonder if somehow the listening port got changed to a different one. Open a command prompt and type the following: "netstat -an|more"

List all the ports that are in state LISTENING and verify if any of them are the correct ones.

Also, what type of security updates did you install?
0
 
LVL 6

Expert Comment

by:Hardeep_Saluja
ID: 22941084
Check to make sure that the security updates have not blocked port 1723 on server.. See what security updates you installed..
Check your firewall or router and make sure port 1723 is listening.. Turn off windows firewall

Please let me know..
Thanks.. Hardeep
0
 
LVL 6

Expert Comment

by:Hardeep_Saluja
ID: 22941121
Also, Check this link.. its bit old but i think could be helpful in your case..

08-067 (KB958644) Patch breaks VPN
http://forums.techarena.in/small-business-server/1062460.htm

As i said above, please check for what security patches you installed ..
0
 The Evil-ution of Network Security Threats

What are the hacks that forever changed the security industry? To answer that question, we created an exciting new eBook that takes you on a trip through hacking history. It explores the top hacks from the 80s to 2010s, why they mattered, and how the security industry responded.

 

Author Comment

by:jhalscott
ID: 22941140
We only installed the Microsoft security updates listed as critical via Windows Update. There are a few ports that are listening that I don't recognize. There really isn't much happening on this server.

How would I verify if any of these are the correct port that PPTP is now listening on?
0
 
LVL 6

Expert Comment

by:Hardeep_Saluja
ID: 22941211
Right.. but sometimes updates can break some things as well.. so pls be sure about it

To verify which port is PPTP listening, please go through
http://www.tek-tips.com/viewthread.cfm?qid=1048826&page=8
Hope this helps.. let me know
0
 
LVL 3

Assisted Solution

by:sukumade
sukumade earned 800 total points
ID: 22941263
To check to see which applications are mapped to a specific port, open up task manager, go to Processes, go to options -> selct columns, and check "PID".

Next open command prompt and type "netstat -anb|more"

Match up the process ID to the port and you will know if the port number has changed
0
 
LVL 6

Expert Comment

by:Hardeep_Saluja
ID: 22941304
Also, there are utilities like pptpsrv and pptpclnt to verify the same
Also, check the pid in cmd using tasklist /svc & compare in task manager for rras service
Or use a tool > Tcp view
0
 

Author Comment

by:jhalscott
ID: 22941449
I rebooted the server after changing the TCP/IP parameters in the Registry to exclude 1723. I don't know if this did it, but after a reboot the port is listening again.
0
 
LVL 6

Accepted Solution

by:
Hardeep_Saluja earned 1200 total points
ID: 22941669
Ok great.. congra8s then.. make sure your vpn is working and you are good to go..

Also, go through this... just for refrence
http://technet.microsoft.com/en-us/sysinternals/bb897437.aspx
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

OpenVPN is a great open source VPN server that is capable of providing quick and easy VPN access to your network on the cheap.  By default the software is configured to allow open access to your network.  But what if you want to restrict users to on…
This is an article about my experiences with remote access to my clients (so that I may serve them) and eventually to my home office system via Radmin Remote Control. I have been using remote access for over 10 years and have been improving my metho…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
Windows 10 is mostly good. However the one thing that annoys me is how many clicks you have to do to dial a VPN connection. You have to go to settings from the start menu, (2 clicks), Network and Internet (1 click), Click VPN (another click) then fi…
Suggested Courses

834 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question