virtualbox.org

Hi (Sorry For My English)
i have a big problem... i have a Win10 Host connect to Lan by a WiFi stick
and a Ubuntu Server in my VirtualBox...

when Starting windows ... Virtual Box see Windows and windows see Virtual Box..
after any time (1hour , 3 hour , 20 min .. not precised) the bridged go down !!!

but when i restart Phical Machine... the Virtual Box Work Finely

have you any Idea ?

The first thing I would do is try a different NIC. The software for USB WiFi devices can be unreliable.