Another Snow Leopard issue; Juniper's Network Connect application (from the great Secure Access series) wouldn't work anymore. It started, but when connecting, it gave the very descriptive error: "Cannot connect!"

Hidden away in the Juniper forums I found the solution:

sudo chmod 755 /usr/local/juniper/nc/6.4.0/
sudo mkdir '/Applications/Network'

6.4.0 being your local version.

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