Comment by saadhud for I just met the same issue and fixed it as the following way. Check the setting of your router.( I assumed you already have the public network, the private network, and the routers.) log in as guest, in the project tab, open the Network dropdown menu and select the Rourter, click the Set Gateway button in the router row. In the External Network menu, choose public. click the set gateway button. still in the Router subtab, click the router, +Add interface. in the subnet menu, select your private network, click the add interface button. Verify that both networks are attached to the router. In the Network tab, choose the Network Topology. private and public should both connect to the router.

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