Cisco AnyConnect 3.1 silent install

This will:

• use native windows tools to detect AnyConnect persistence
• skip AnyConnect installation if other version is intalled
• uninstall AnyConnect wherever it is installed including custom directory or different drive
• uninstall it on 32-bit or 64-bit windows

This is tested on:

anyconnect-win-3.1.05187-pre-deploy-k9.msi

b260a31b6970073d6157aca648ac5d14

875bbbdd86a65f5c5dab3e3d173fefb00b2f2e1f