Unfortunately, the documentation from Cisco is extremely confusing, and I’ve seen a lot of organizations that do it wrong (by which I mean insecurely). The process itself is quite simple, though, so let’s go through the steps you’ll need to configure Cisco AnyConnect for your VPN. Configure AAA authentication.
- Although it does not appear in the process list, you can see it by opening sockets with TCPview (sysinternals). When you terminate this process, normal operation of AnyConnect returns. Problem: You receive an “Unable to Proceed, Cannot Connect to the VPN Service” message. The VPN service for AnyConnect is not running.
- Note: Make sure that port 443 is not blocked so the AnyConnect client can connect to the ASA. When a user cannot connect the AnyConnect VPN Client to the ASA, the issue might be caused by an incompatibility between the AnyConnect client version and the ASA software image version.
Objective
The objective of this document is to show you basic troubleshooting steps on some common errors on the Cisco AnyConnect Secure Mobility Client. When installing the Cisco AnyConnect Secure Mobility Client, errors may occur and troubleshooting may be needed for a successful setup.
Note that the errors discussed in this document is not an exhaustive list and varies with the configuration of the device used.
For additional information on AnyConnect licensing on the RV340 series routers, check out the article AnyConnect Licensing for the RV340 Series Routers.
Software Version
AnyConnect v4.x (Link to download)
Basic Troubleshooting on Cisco AnyConnect Secure Mobility Client Errors
Note: Before attempting to troubleshoot, it is recommended to gather some important information first about your system that might be needed during the troubleshooting process. To learn how, click here.
1. Problem: Network Access Manager fails to recognize your wired adapter.
Solution: Try unplugging your network cable and reinserting it. If this does not work, you may have a link issue. The Network Access Manager may not be able to determine the correct link state of your adapter. Check the Connection Properties of your Network Interface Card (NIC) driver. You may have a 'Wait for Link' option in the Advanced Panel. When the setting is On, the wired NIC driver initialization code waits for auto negotiation to complete and then determines if a link is present.
2. Problem: When AnyConnect attempts to establish a connection, it authenticates successfully and builds the Secure Socket Layer (SSL)session, but then the AnyConnect client crashes in the vpndownloader if using Label-Switched Path (LSP) or NOD32 Antivirus.
Solution: Remove the Internet Monitor component in version 2.7 and upgrade to version 3.0 of ESET NOD32 AV.
3. Problem: If you are using an AT&T Dialer, the client operating system sometimes experiences a blue screen, which causes the creation of a mini dump file.
Solution: Upgrade to the latest 7.6.2 AT&T Global Network Client.
4. Problem: When using McAfee Firewall 5, a User Datagram Protocol (UDP)Datagram Transport Layer Security (DTLS) connection cannot be established.
Solution: In the McAfee Firewall central console, choose Advanced Tasks > Advanced options and Logging and uncheck the Block incoming fragments automatically check box in McAfee Firewall.
5. Problem: The connection fails due to lack of credentials.
Solution: The third-party load balancer has no insight into the load on the Adaptive Security Appliance (ASA) devices. Because the load balance functionality in the ASA is intelligent enough to evenly distribute the VPN load across the devices, using the internal ASA load balancing instead is recommended.
6. Problem: The AnyConnect client fails to download and produces the following error message:
Solution: Upload the patch update to version 1.2.1.38 to resolve all dll issues.
7. Problem: If you are using Bonjour Printing Services, the AnyConnect event logs indicate a failure to identify the IP forwarding table.
Solution: Disable the Bonjour Printing Service by typing net stop “bonjour service” at the command prompt. A new version of mDNSResponder (1.0.5.11) has been produced by Apple. To resolve this issue, a new version of Bonjour is bundled with iTunes and made available as a separate download from the Apple web site.
8. Problem: An error indicates that the version of TUN or network tunnel is already installed on this system and is incompatible with the AnyConnect client.
Solution: Uninstall the Viscosity OpenVPN Client.
9. Problem: If a Label-Switched Path (LSP) module is present on the client, a Winsock catalog conflict may occur.
Solution: Uninstall the LSP module.
10. Problem: If you are connecting with a Digital Subscriber Line (DSL) router, DTLS traffic may fail even if successfully negotiated.
Solution: Connect to a Linksys router with factory settings. This setting allows a stable DTLS session and no interruption in pings. Add a rule to allow DTLS return traffic.
11. Problem: When using AnyConnect on some Virtual Machine Network Service devices, performance issues have resulted.
Solution: Uncheck the binding for all IM devices within the AnyConnect virtual adapter. The application dsagent.exe resides in C:WindowsSystemdgagent. Although it does not appear in the process list, you can see it by opening sockets with TCPview (sysinternals). When you terminate this process, normal operation of AnyConnect returns.
12. Problem: You receive an “Unable to Proceed, Cannot Connect to the VPN Service” message. The VPN service for AnyConnect is not running.
Solution: Determine if another application conflicted with the service by going to the Windows Administration Tools then make sure that the Cisco AnyConnect VPN Agent is not running. If it is running and the error message still appears, another VPN application on the workstation may need to be disabled or even uninstalled. After taking that action, reboot, and repeat this step.
13. Problem: When Kaspersky 6.0.3 is installed (even if disabled), AnyConnect connections to the ASA fail right after CSTP state = CONNECTED. The following message appears:
AnyConnect VPN Client FAQ
Solution: Uninstall Kaspersky and refer to their forums for additional updates.
14. Problem: If you are using Routing and Remote Access Service (RRAS), the following termination error is returned to the event log when AnyConnect attempts to establish a connection to the host device:
Solution: Disable the RRAS service.
15. Problem: If you are using a EVDO wireless card and Venturi driver while a client disconnect occurred, the event log reports the following:
Solutions:
- Check the Application, System, and AnyConnect event logs for a relating disconnect event and determine if a NIC card reset was applied at the same time.
- Ensure that the Venturi driver is up to date. Disable Use Rules Engine in the 6.7 version of the AT&T Communications Manager.
Cisco Vpn Will Not Connect
If you encounter other errors, contact the support center for your device.
For further information and community discussion on AnyConnect licensing updates, click here.
For AnyConnect Licensing FAQs, click here.