I’m sure there are quite a few people in the world that have ran across the same roadblock I did. Updating from a previous version of Apple OS X, and finding you are not able to use Dell SonicWall NetExtender to connect to their work’s VPN connection. I held off of updating until yesterday, and hit that a much needed time. I figure I’ll share an easy fix to those that need it.
The El Capitan version brings more security, and a filesystem protection layer. This gets in the way of changes that NetExtender needs to do in order to clean itself up for the new version. To get around this, you can reboot your computer and when you hear the Apple boot chime, press command-R. I don’t know if you hit it once or hold it, as by very nature I hold it until the screen appears. What will come after a bit is a recovery mode OS X. Go to the bar at the top and select Utility -> Terminal and type “csrutil disable”. Then select the apple icon in the upper-left and reboot. Once your system is back up, start the NetExtender as you normally would, and attempt your login. It should prompt you for an administrator login to make the changes as it’s doing so. Once that’s done, it will connect and you can disconnect and close out. Reboot, and once you hear the Apple startup chime again press command-R. Once you are in the recovery mode desktop, on the top bar select “Utility” then “terminal” as last time. Type “csrutil enable” to enable the filesystem protection once more. Then, select the apple icon in the upper-left and reboot. You should be good now.
Some people have said that they needed to change the permissions of /usr/sbin/pppd but I have not needed this. It looks like El Capitan is automatically placing pppd into the wheel group, and adding a suid bit to it to allow it to do what it needs to do.
Thanks, and have a great one!