This error can occur if you have certain versions of Kaspersky Anti-Virus (or Kaspersky Internet Security) installed and is a known issue with Kaspersky and the AnyConnect client. This issue can be resolved by configuring an exception in Kaspersky to trust the Cisco AnyConnect client.
Test whether Kaspersky is blocking the VPN session
- Temporarily stop Kaspersky by right clicking on the Kaspersky icon in the task bar and select Pause Protection.
- In the Pause protection window click on Resume protection in...1 minute.
- Try connecting to the VPN Network Service whilst Kaspersky is temporarily stopped.
If the VPN session can now be successfully established then Kaspersky is blocking the establishment of the VPN session, and this can be resolved by adding the Cisco AnyConnect client as a trusted application to Kaspersky.
In order for the Cisco AnyConnect client to successfully establish a VPN session, it needs to be added as a trusted application to Kaspersky. (The following instructions are for configuring Kaspersky Anti-Virus 6, but should provide a guide for configuring other Kaspersky versions.)
- Open the Kaspersky application settings, either by clicking on the Settings button from the Kaspersky application window, or by right clicking the Kaspersky icon in the task bar and select Settings.
- In the settings window click on the Trusted zone... button.
- In the trusted zone window select the Trusted application tab and click on the Add... button. (Note there may be some application listed here already.)
- In the trusted application window click on the Browse button and then select Applications from the drop down menu.
- From the list of applications select the vpnagent.exe program. (Alternatively select Browse from the trusted application window and locate the vpnagent.exe program, which is normally located in the "C:\Program Files\Cisco\Cisco AnyConnect VPN Client" folder on My Computer.)
- In the trusted application window, tick the Do not scan network traffic box and ensure the other boxes are not ticked.
- Click on OK to close the trusted application window, click OK to close the trusted zone window and click OK to close the settings window.