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


VPN access not working

Posted on 2011-10-23
Medium Priority
Last Modified: 2012-05-12
Hi all,

One of the users of our remote branch office failed to get vpn connection. Untill yesterday, the vpn connection was working fine. The error code is 721. That remote branch office network is a workgroup based network. I tried my username through VNC and the same error happened. So i disabled the firewall and tried the vpn again. But still no access is permitted. Please help.
Question by:TsvTech
LVL 10

Expert Comment

by:Arman Khodabande
ID: 37015541
Take a look at this.
I don't know if you've tried the suggestions in this Article.

Expert Comment

ID: 37019037
I concur! Which VPN, software are you using?

Author Comment

ID: 37022292
We are using windows XP vpn client.Without changing anything on the network firewall,today morning it started working. So this is the problem. Some days,vpn doesnt work and in another days, it starts working with same network configuration,same users and same computer. There are 2 computers in the network and the second one is not connected to the VPN either. The internet speed is very slow( 1.5 Mbps/256 Kbps maximum).
Get quick recovery of individual SharePoint items

Free tool – Veeam Explorer for Microsoft SharePoint, enables fast, easy restores of SharePoint sites, documents, libraries and lists — all with no agents to manage and no additional licenses to buy.

LVL 10

Accepted Solution

Arman Khodabande earned 2000 total points
ID: 37025532
According to Microsoft :

This issue may occur if the network firewall does not permit Generic Routing Encapsulation (GRE) protocol traffic. GRE is IP Protocol 47. PPTP uses GRE for tunneled data.


To resolve this issue, configure the network firewall to permit GRE protocol 47. Also, make sure that the network firewall permits TCP traffic on port 1723. Both of these conditions must be met to establish VPN connectivity by using PPTP.

For more information about the GRE protocol and other configs refer to that KB article in my first post.
LVL 10

Expert Comment

by:Arman Khodabande
ID: 37165817
Hi LeeTutor!

My comment (http://#37025532) is the only solution and it's a 90-percent-working solution, according to this KB article from Microsoft.
LVL 59

Expert Comment

ID: 37218535
This question has been classified as abandoned and is closed as part of the Cleanup Program. See the recommendation for more details.

Featured Post

A Cyber Security RX to Protect Your Organization

Join us on December 13th for a webinar to learn how medical providers can defend against malware with a cyber security "Rx" that supports a healthy technology adoption plan for every healthcare organization.

Question has a verified solution.

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

Configuring network clients can be a chore, especially if there are a large number of them or a lot of itinerant users.  DHCP dynamically manages this process, much to the relief of users and administrators alike!
For both online and offline retail, the cross-channel business is the most recent pattern in the B2C trade space.
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
Course of the Month18 days, 20 hours left to enroll

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