@David-TP Service provider: Italian postemobile (virtual using vodafone infrastructure) Router version: TL-MR6400(EU)_V3 Beta firmware: how to get it? Strange thing, a few days ago the VPN connection...

Router is used in 3G/4G mode. My internet provider is using MTU size 1392; The default size of WLAN interface of the router is 1500 and this makes me troubles with VPN and remote desktop of Windows....