A knowledge base article about bSecure GlobalProtect VPN: macOS High Sierra and Newer (10.13+) Fails to Connect provided by the UC Berkeley IT Service Hub - Knowledge Portal
NOTE: This issue only relates to devices with the Intel chipset, Mac laptops and desktops using the M1 chip do not experience this issue.
With enhancements implemented by Apple to provide better protections within MacOS X 10.13 and newer releases some software takes additional configuration to work correctly.
If you have successfully connected before please see article KB0013671
When the software is run the first time after installation the user may see a popup reporting that a system extension has been blocked. When this happens the user then has 30 minutes to open System Preferences, click on the Security and Privacy icon, and then click on the “Allow” button near the bottom of the window (see https://developer.apple.com/library/archive/technotes/tn2459/_index.html#//apple_ref/doc/uid/DTS40017658-CH1-TNTAG2 for more information). This should enable the GlobalProtect software (you may need to restart so the software can start correctly after being blocked by the system.)
If the user does not perform the above actions within 30 minutes of seeing the popup the approval button will disappear and the steps necessary to enable the software become more intricate.
Warning: These steps are for advanced technical users, if you are not comfortable working on the command line of your computer we recommend you see technical assistance either with your local desktop support representative or at a local Apple Genius Bar.
This should correct most issues related to the GlobalProtect client on MacOS X.