There are a number of problems getting the Juniper Network Connect VPN client running on the Mac. The permissions on directories are not correct after install, there are issues with the 64 bit kernel, problems if VMWare or Parallels is installed, etc. These instructions are the result of research I did to get Network Connect 6.2.0 running on OS X 10.6.8 (Snow Leopard). If you have Network Connect installed already you should uninstall it completely.

To Remove Network Connect
You may not have some of the files listed to run or remove and you can just skip those steps. You should review these steps carefully particularly if you have other Juniper products installed. They remove directories that may include installations of other Juniper products. These instructions should be run from your home directory.

1. sudo /usr/local/juniper/nc/install/uninstall_nc.sh
2. sudo rm -R /Applications/Network Connect.app
3. sudo rm -R /usr/local/juniper
4. sudo rm -R /Library/Frameworks/net.juniper.*
5. sudo rm -R /Library/Internet Plug-ins/net.juniper.*
6. sudo rm -R /Library/Widgets/Network Connect.wdgt
7. sudo rm /private/var/db/receipts/net.juniper.*
8. rm -R Library/Application Support/Juniper Networks
9. rm -R Library/Caches/net.juniper.NetworkConnect
10. rm Library/Preferences/net.juniper.NetworkConnect.plist
11. rm -R Library/Logs/Juniper Networks

To Install Network Connect

1. Download NetworkConnect.dmg. I was unable to get the applet installer from the VPN login to work correctly. You can download the dmg file directly from your vpn site. Add the path “/dana-cached/nc/NetworkConnect.dmg” to your VPN URL. If your VPN login is at https://vpn.mycompany.com/… then you would download from https://vpn.mycompany.com/dana-cached/nc/NetworkConnect.dmg. You may have to login to the VPN site to access the download.
2. Open NetworkConnect.dmg and run the installer. If you get an error saying there is already a version installed do the uninstall steps above.
3. sudo chmod 755 /usr/local/juniper/nc/[version number]
4. sudo mkdir ‘/Applications/Network Connect.app/Contents/Frameworks’
5. If you have VMWare or Parallels installed you will have to deactivate the network interfaces they add. If you don’t do this you will probably be able to connect but have a very high packet loss rate. You may have similar issues with other products that interact with routing. To do this go to ‘System Preferences -> Network’ and change ‘Configure IPv4’ to ‘off’ for these extra interfaces. They will typically be named something like ‘Ethernet Adaptor (en2)’. Entries like these in the Network Connect log are indicative of this type of problem:

           rmon.warn adding back the missing route to 0.0.0.0/0.0.0.0 with gw 0.0.0.0, metric 1, if_id 9
           rmon.info Adding route: 0.0.0.0/0.0.0.0 -> 0.0.0.0 (metric:1) (if_id:9)
           rmon.warn deleted route to 0.0.0.0/0.0.0.0 with gw 0.0.0.0, if_id 7  reappeared
           rmon.info Deleting route: 0.0.0.0/0.0.0.0 (routemon.cpp:1979)
           rmon.error Failed to delete route. No such process (routemon.cpp:1014)

6. sudo chmod 4711 /usr/local/juniper/nc/[version number]/ncproxyd
7. If your kernel is running in 64 bit mode you will have to change it to 32 bit mode. This may no longer be true with newer versions of Network Connect but it is for version 6.2.0. You can change the kernel to 32 bit mode temporarily by shutting down then holding the 3 and 2 keys down while starting up.

You should now be able to launch Network Connect from Applications. Since you did not use the applet installer you will have to enter your VPN URL. This does not include the path part of the URL. For example: https://vpn.mycompany.com.