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If IPsec is not blocked, but IPsec-over-HTTPS is being used anyway, you should check the Advanced VPN Client profile in the submenu Advanced IPsec Options to see if UDP encapsulation is activated and the port is set to 444. In this case, enter the port 500 and switch to Standard IPsec. Please also see this article in our Knowledge Base.
Low performance without split tunneling:
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For more information and setup instructions, see this article in our Knowledge Base.
Check the load on the Internet connections:
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