Big Sur upgrade incompatible with VPN

I had a query on LibAnswers this morning about Big Sur. A UC Merced postdoc in Europe upgraded his laptop to Big Sur, and now the VPN won't work for him and he can't get into the databases. I upgraded my personal device to Big Sur last night, and tried to access the VPN. No luck. I get this "Connecting ..." message that just keeps going and going. Thoughts? Answers? Please?