From the Intego Menu
From NetBarrier Preferences
Open NetBarrier and click the word 'NetBarrier' in the top menu bar. Choose Preferences from the drop down menu and click the General icon in the new window that appears.
Now, toggle the 'Off' switch and enter your macOS admin password if prompted to do so. Your software will be disabled until you manually enable it again.
For macOS Big Sur Users
If you are running macOS Big Sur 11.0 or higher, then there is an additional step necessary to disable NetBarrier completely.
Open System Preferences > Network:
Highlight the NetBarrier Extension in the left column, and select the option Make Service Inactive. Now click Apply to save the changes.
You can enable NetBarrier again using the same process: