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Closing PPTP on 1723

To know about PPTP go to : http://en.wikipedia.org/wiki/Point-to-Point_Tunneling_Protocol 
Basically PPTP is used as method to connect and implement VPN (Virtual Private Networks). There have been other protocols as well for example, IPSec. PPTP has been often criticized for its well known vulnerabilities, like weak encryption etc. But I am not concerned with all these, my challenge was to explore the ways to close the PPTP(Port 1723) on a machine (Windows XP). I did a lot of googling around on the web for hours but was unable to find any satisfying solution. Most results were related to how to setup a VPN connection using PPTP on a Windows client machine. But my question was how to close port 1723 (PPTP), if already your machine is acting as VPN server?
So, I started other way round. I setup my machine as a VPN server. Steps are very simple:
1. Go to Network connections
2. Click on "Create a new connection" wizard
3. Select "Set up an advanced connection". Click Next.
4. Select "Accept Incoming connections". Click Next.
5. Select "Allow virtual private connections" Click Next.
6. Select the users for the list to grant permission. Click Next.
7. Click Next, and Finish.
You will see an Incoming Connection icon in network connections dialog.
 Simultaneously I started to scan my PC for port 1723, and I found it open:
 Now, right click on Incoming Connections icon in network connections dialog, choose properties, go to general tab and uncheck "Allow other users to make private connections on my computer......" under Virtual Private Network section.
Now again scan the port 1723:
This is the most suitable approach I have found to close the port 1723 on Win XP.
Still I don't know how to disable this service from Services.msc, so I shall continue to use above approach. If you know, any other ways to close it, it will be greatly appreciated, if you let me know.

Update: The 1723 can also be stopped by stopping "Routing and Remote Access" services under "Services.msc"



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