Have you had any luck in finding a solution? I am experiencing the same thing. I am running Forticlient VPN (IPSEC) ver 7.0.9.0493 with Windows 10 Pro. I can connect via hot spots, other wifi connections but have isolated it to one site that is using a Sonicwall TZ500. If I bypass their Sonicwall and connect directly to their WAN I can connect.
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