Updated about 13 yrs, 3 mths ago (August 30, 2011). Know a better answer? Let me know!

Fixing error 720 on an SsTP VPN

Fixing Error 720 on a Server 2008/2008 R2 Secure Socket Tunnelling Protocol (SSTP) VPN.

I’m unsure how common this problem is, or how specific to me… but it took a lot of figuring out, so in the hope that it helps someone else…

I have Server 2008 R2 running the Routing and Remote Access role to serve as an SSTP (Secure Socket Tunnelling Protocol) VPN server so my Windows 7 laptop can connect to it. I recently changed my hardware router for a different router, and ever since, was receiving “Error 720: “ when trying to connect to the VPN.

After a dismally long time trying pointless other things, I fixed the problem by going to the Routing and Remote Access settings (run rrasmgmt.msc on the VPN server), right clicking on the server name and selecting Properties, navigating to the IPv4 tab, and changing “Dynamic Host Configuration Protocol (DHCP)” to “Static address pool”, and entering a valid IP range in there.

These are the errors I was experiencing prior to this:

Error 720: A connection to the remote computer could not be established. You might need to change the network settings for this connection.

CoId={F06425E8-D193-48B8-A55C-A2774D53B684}: The user  <username> connected to port VPN0-127 has been disconnected because no  network protocols were successfully negotiated.

Log Name:      System
	Source:         RemoteAccess
	Date:           9/12/2009 9:45:53 AM
	Event ID:      20253
	Task Category: None
	Level:         Error
	Keywords:      Classic
	User:          N/A
	Computer:       <removed>
	Description:
	CoId={8101141A-FCD0-477D-9EC4-E3B2C4CDE6AB}: The user  <username> connected to port VPN0-127 has been disconnected because no  network protocols were successfully negotiated.
	Event Xml:
	<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
	<System>
	<Provider  Name="RemoteAccess" />
	<EventID  Qualifiers="0">20253</EventID>
	<Level>2</Level>
	<Task>0</Task>
	<Keywords>0x80000000000000</Keywords>
	<TimeCreated  SystemTime="2009-12-08T23:45:53.000000000Z" />
	<EventRecordID>4011</EventRecordID>
	<Channel>System</Channel>
	<Computer><computer name> </Computer>
	<Security />
	</System>
	<EventData>
	<Data>{8101141A-FCD0-477D-9EC4-E3B2C4CDE6AB}</Data>
	<Data><username></Data>
	<Data>VPN0-127</Data>
	</EventData>
</Event>

More Information

For more information about:

Secure Socket Tunneling Protocol (SSTP), see en.wikipedia.org/wiki/Secure_Socket_Tunneling_Protocol
Windows Server 2008 R2, see microsoft.com/windowsserver2008/en/us/default.aspx

Updated about 13 yrs, 3 mths ago (August 30, 2011). Know a better answer? Let me know!

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User submitted comments:

Alan Singfield, about 14 yrs, 7 mths ago
Monday May 10, 2010 11:14 AM

Thanks, this solved my problem - it looks like the DHCP doesn't seem to work very well.

John Vajda, about 14 yrs, 7 mths ago
Thursday May 13, 2010 5:41 AM

Wow, MANY THANKS for taking the time to post this. It solved my problem.

I too had installed a new router, and my vpn connection started failing with an error code of 720. Event ID 20253 appeared in the System event log of the vpn server as described above. I could tell that the Windows 7 pptp (or actually sstp) server was the culprit, not the client. Interestingly, when I reverted to troubleshooting by using old router, the problem persisted.

In Windows 7, there is no rrasmgmt.msc snapin. Simply go into Control Panel -> Network and Internet -> Network and Sharing Center -> Change Adapter settings. Select "Incoming Connections", right-click and go into Properties, and select a static address pool for IPv4.

Ed A, about 14 yrs, 6 mths ago
Thursday June 10, 2010 7:14 PM

Just found this by chance after hours searching on Google and going through tons of bad advice. Thank you!

Marek, about 13 yrs, 9 mths ago
Sunday March 6, 2011 1:00 PM

Many thanks, I spending days searching on Google and MS forum

Michael, about 13 yrs, 9 mths ago
Monday March 21, 2011 12:24 AM

Excellent. Fixed my problem. Why can't the error log say it's having trouble allocating an IP address, rather than being so obtuse, eh?

Mohsen Heydari, about 13 yrs, 7 mths ago
Thursday May 12, 2011 9:25 AM

Thanks a lot! i couldn't fix my problem without that info

Drmaster, about 13 yrs, 4 mths ago
Tuesday August 9, 2011 9:13 AM

YES!!!! It is WORK!!!! Thanks!!!!
(win 2008 server r2 x64 instaled on vmware work-on, TMG)

hernadi, about 13 yrs, 2 mths ago
Sunday September 25, 2011 9:46 AM

To fix error 720 :
C:windowssystem32sfc.exe /scannow, and then restart.

hernadi, about 13 yrs, 2 mths ago
Sunday September 25, 2011 9:48 AM

To fix error 720 :
C:windows system32 sfc.exe /scannow, and then restart.

Rico, about 12 yrs, 11 mths ago
Friday January 6, 2012 2:03 AM

You are a Champ, it worked for me too :-)

Thanks a million.

Ramon, about 12 yrs, 8 mths ago
Saturday March 24, 2012 1:15 AM

Thank you so much, I was about to give up and that solved my issue immediately. My router does not support GRE so I had to turn to SSTP, but my server hostname is not externally routable.
I went ahead go a new domain, and a new ssl certificate and was about to go crazy if this did not work. Thank you for your assistance.

Fadi Sarsak, about 12 yrs, 2 mths ago
Tuesday October 9, 2012 7:40 PM

thank you very much, as every one else i was about to give up and the error 720 was driving me crazy. now users can connect to VPN.

thanks a trillion again

Martijn, about 12 yrs, 20 days ago
Saturday December 1, 2012 12:45 AM

But I *do* want to use DHCP...

Jason, about 11 yrs, 10 mths ago
Saturday February 16, 2013 6:01 AM

Thank you this helped me a lot. I found out that it was the Static address i assigned my server from the DHCP server. since the request came from the same mac the server kept giving it the same IP address. when i removed my DHCP reservation and turned it back to DHCP on the VPN server everything worked perfectly.

Erik, about 11 yrs, 5 mths ago
Thursday July 11, 2013 7:54 PM

Finally something that worked!

nt.archie, about 11 yrs, 4 mths ago
Tuesday August 20, 2013 8:11 PM

Good job! It would be nice to see a real solution to this issue on technet :/ not a workaround (disabling DHCP is not a nice thing to do).

Doalwa, about 9 yrs, 9 mths ago
Tuesday March 10, 2015 2:45 PM

Thanks a ton, man!

Doalwa, about 9 yrs, 9 mths ago
Tuesday March 10, 2015 2:45 PM

Thanks a ton, man!

Doalwa, about 9 yrs, 9 mths ago
Tuesday March 10, 2015 2:45 PM

Thanks a ton, man!

Galip M. Ermis, about 9 yrs, 8 mths ago
Wednesday April 1, 2015 3:43 AM

First I used a static pool, then it just started to work, thx. Then I reverted it back from static to dhcp. Now I'm using DHCP to lease addresses. Weird problem. It's kind of a bug or something. Still exists in 2012 R2

Clemilton, about 9 yrs, 4 mths ago
Thursday August 13, 2015 2:36 PM

Perfect!!! After weeks looking for a solution, this is the one that solved the problem!!! Thank you for sharing!!!

Victor Wong, about 7 yrs, 9 mths ago
Wednesday March 8, 2017 3:49 AM

5 years later, still saved my life. Thanks a lot.

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