Cisco VPN Client not working with Vodafone 3g dongle?

We’ve recently been approached by a client to provide a remote access solution for travelling representatives. RSCC provide IT support for them in their office in Letchworth, but they needed to extend the reach of their network to travelling representatives. As they require access to a data-heavy database and had limited upstream bandwidth, VPN access itself wouldn’t cut it, so we’ve put together a solution utilising laptops with mobile 3g cards, a Cisco VPN and a Windows 2008
terminal server.

I’ve just spent a few happy hours this morning trying to figure out why my test laptop wouldn’t connect to the Cisco VPN when using the Vodafone dongle. It would connect and complete x-auth, but no data would pass.

The usual cause for cisco/mobile card issues is NAT Traversal – this needs to be enabled on the firewall/router for the client to work over a mobile card, however after checking and double checking, this turned out not to be the cause in this case.

I decided to bypass my prime suspect – the Vodafone Connect software, by setting up a dial-up connection using the dongle as a modem (to do so, set the dial-up number to *99# and use the username/password: web/web This instantly fixed the issue, allowing the VPN client to connect, and suprisingly snappy access to the terminal server.

A bit more research shows that the problem was not Vodafone connect, but actually Cisco’s lack of support for the new NDIS 6.2 driver model used by Windows 7. Judging by how long we had to wait for a 64-bit IPSEC client, I’m not holding my breath for an update.

On the positive side, the windows dial-up client takes only a second or two to connect, wherease the supremely bloated Vodafone client takes some 20-30 seconds to start up & connect. Unfortunately I’m going to have to find another way
of monitoring the data usage as the windows client does not do this.

Update 27/04/2012.

This has proved to be quite a popular post, here’s a couple of other bits to look for that we see come up every now & again, which can result in the same problem, though not specific to mobile cards (ie connection but no data passing).

1. Check that your local LAN and the remote LAN aren’t trying to use same IP subnet. (quite common if the corporate network is using 192.168.0.x). This will break the routing – the solution is to change your local (client end) lan subnet to something else like for example 192.168.10.x or 172.16.1.x

2. Some low end routers have issues with passing through multiple IPSEC tunnels. Try disconnecting any other devices using IPSEC at the client end. If this fixes the issue, try a firmware upgrade for the router, or a better router.

29 thoughts on “Cisco VPN Client not working with Vodafone 3g dongle?

  1. We’ve been looking for a solution for months. Vodafone couldn’t help us and I couldn’t find anything at Cisco. Which is actually quite strange.
    It works now for all Windows 7 users with a Vodafone dongle in our office.
    Thank you very much!

    The Netherlands

  2. Cheers for this – I have been trying to figure this out for ages and suspected a driver issue but didn’t know where to turn! HERO!

  3. Yeah Great… Unfortunatley doesn’t work. Cisco anyconnect, win7 x64, win7 x86, Dell Laptop with internal Vodafone 3g and with external Vodafone USB 3g dongle. I get through the authentication. Through initiating connection, through examining system, through activating vpn, through configuring systems then it disconnects me. With Dell software, Vodafone software, Even through the windows dialup route. 🙁

  4. Cheers Richard for sharing that with us!! This has been driving me crazy. we tried every version of vodafone software, different models of dongles, changing sim cards, disabling proxy scripts… etc etc… never thought to try the above.
    Now works a treat in VPN and with proxy on. 🙂

  5. Amazing buddy , its almost after a year of your initial post that there was a need for me .
    Thank you ! you saved my day 🙂

  6. Ah yes, this issue puzzled me as we had 32-bit Win7 laptop and that worked fine, but 64-bit one would discard/not receive any packets

    Dial-up connection has solve this, fantastic!

  7. It works but since the connection is not over 3G, speed will be slow. So to get the vpn connection work for cisco vpn client version 5, you need to update your DNE and try it out.

    Google search for “vodafone mobile connect readme” click on the first link and go to the general section of “Known Issues and Limitations”. It clearly says that.


  8. This issue was driving me crazy for weeks… Neither Vodafone nor my IT was able to solve the issue.

    Thank you very much. Cheers….


  9. Before slaying Vodafone here too much, I would like to add that I encountered this problem with a Telstra 3g dongle. Above article proved to be the resolution. Thanks again, this is one of the most helpful posts ever.

  10. When I connect to VPN server using Vodafone Dongle, in safari browser and Skype are stop to working internet means both internet and VPN connection not works together

  11. Hi Kalpesh, that’s likely to be a split-tunneling issue at your firewall end. You’d need to either enable split tunnelling, or configure your firewall policy to allow hairpinning for the web traffic.

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