Fixing when GlobalProtect VPN for Mac is stuck in a “connecting” state or does nothing
If your Mac is running a newer version of the macOS (i.e., Catalina, Mojave, High Sierra, Sierra) and when you click Connect nothing seems to happen, you might need to adjust your macOS security settings.
Go to Apple > System Preferences > Security and Privacy > General. If you see an alert about software from Palo Alto Networks being blocked, click Allow, then close your preferences window.
If prompted, enter your computer's administrative user name and password. If you don't have administrative rights to your University-owned computer, contact your departmental tech support personnel.