System Preferences / Network
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Connections to internet more or less fine, but after a couple of days when I thought I ought to check the Network settings, I had a problem.
As soon as I select Network, it opens but a box drops down saying......... "Your Network settings have been changed by another application"
The only button offered is "OK" but when this is clicked it disappears momentarily but immediately returns. As a consequence I cannot access 'Network'.
Access to internet is possible but the odd glitch, hence I need to get at the settings.