I have been struggling to figure out why the Cisco AnyConnect VPN on my MacBook Air stopped working a couple of months ago. Access from my iPhone and iPad were fine but from my MacBook Air, AnyConnect kept disconnecting. The Cisco support forum and Google search is only as good as the search criteria you enter. Well, finally I found the answer to this frustrating issue especially as I was planning to work remotely during the Christmas break.

The problem rears it's ugly head when you enable the "Back to my Mac" application in MobileMe or iCloud. Both the "Back to my Mac" and Cisco AnyConnect VPN use a virtual adapter with the same name "utun0". Since MobileMe or iCloud initiates when your Mac starts up, it grabs the utun0 interface first, causing the Cisco AnyConnect VPN to connect and then disconnect immediatly. I know many Mac users have had this same issue so hope this post helps. Have you had problems with the Cisco Anyconnect VPN?