MacOs Ventura 13.7.8 (Intel x86 64) X CISCO Client VPN 5.1.20.333

Hi,

Google AI says:

The most likely cause for Cisco Secure Client (version 5.1.20.333) crashing immediately upon launch on macOS Ventura is an issue with the background daemon (vpnagentd), orphaned preference files from the previous version, or blocked system/socket extensions.

Because the installer completed successfully, the underlying system binaries are present, but the GUI application is failing to handshake with the background service or is reading a corrupt preference file. Follow these structured steps to resolve the issue.

1. Reset Leftover Preferences and Cache

Upgrading Cisco clients on macOS frequently leaves behind conflicting application states. Clearing these often resolves instantaneous startup crashes.

1. Completely quit the app if it's running in the background.
2. Open Finder, press Cmd + Shift + G, and navigate to:
3. /opt/cisco/secureclient/vpn/
4. Delete any corrupted profile or preferences XML files (such as preferences.xml or custom .xml files). Note: You may want to back them up to your desktop first.
5. Go to ~/Library/Preferences/ and look for any file containing com.cisco.Cisco-Secure-Client or com.cisco.anyconnect, then move them to the Trash.

2. Verify and Force Start the Background Daemon

The GUI client will instantly close or flash if the underlying macOS daemon (vpnagentd) is not active.

1. Open the Terminal app.
2. Check if the service is running by executing:
3. bash

sudo launchctl list | grep cisco

1. Be careful using code.
2. If it is missing or not responding, force-load the daemon with the following command:
3. bash

sudo launchctl load -w /Library/LaunchDaemons/com.cisco.secureclient.vpnagentd.plist

1. Be careful using code.
2. (For older upgrade paths, the path might still be /Library/LaunchDaemons/com.cisco.anyconnect.vpnagentd.plist).

3. Check System Extension Approvals

macOS Ventura strictly enforces security gates on Network Extensions. If the Socket Filter or Core VPN extension failed to prompt for administrative privileges during the installation, the client will immediately exit on launch.

1. Go to Apple Menu  > System Settings > Privacy & Security.
2. Scroll down to the Security section.
3. Look for a message stating "System software from application 'Cisco Secure Client' was blocked from loading." 
4. Click Allow and enter your macOS administrator password.
5. Restart your MacBook Pro to allow the kernel extension to attach successfully.

4. Perform a Clean Reinstallation

If the steps above do not stop the flashing crash, the installation package might have misconfigured modules for your Intel architecture. Use the built-in uninstaller rather than dragging the app to the trash to completely purge system extensions.

1. Navigate to /Applications/Cisco/ and double-click Uninstall Cisco Secure Client.
2. Follow the prompt to remove all components and restart your Mac.
3. Re-run the version 5.1.20.333 installer package. When selecting modules, ensure only the VPNcomponent and DART (Diagnostics and Reporting Tool) are selected if you do not use other Cisco services like Umbrella or ISE Posture

VPN:

A virtual private network, or VPN, is a private connection over the Internet from a device to a specific network.  VPN technology is widely used in corporate environments. If you need to be "present" on an institutional network, a VPN is a great tool for accomplishing this. It is generally issued and controlled by the institution.

Almost all other uses are a SCAM. There is generally no need for you to have a private (and almost always MUCH slower) connection to a VPN vendor's Network, except to make it easier for them to harvest your data to sell. If you are behind a Router you control or Trust, there is NO security advantage whatsoever in using a VPN. Your connections are already encrypted in most cases.

If VPN vendors just stopped there, it would be bad. But many of these packages also insist on scanning all your files, non-stop, -- nominally looking for viruses, but who knows for sure what data they are harvesting. Their non-stop file reading punishes your computer's performance in the process.

Some also break into your other secure connections so they can be FIRST to examine your data, often leaving your Mac MORE vulnerable to attack.

What VPN service to use?

DON'T use VPN services

https://gist.github.com/joepie91/5a9909939e6ce7d09e29