Hi Julien, thank you for using our forum, my name is Luis I am part of the Small business Support community. In this case I suggest you to check the firewall setting of each host, below you will find a link with some tips to configure the firewall settings in Windows.
Article ID:5728 Configure a Teleworker VPN Client on the RV34x Series
Router Objective The Teleworker VPN Client feature minimizes the
configuration requirements at remote locations by allowing the device to
work as a Cisco VPN hardware client. When the T...
Article ID:5708 Configure the LAN and DHCP Settings on the RV34x Series
Router Objective A Local Area Network (LAN) is a network limited to an
area such as a home or small business that is used to interconnect
devices. LAN settings can be configured to li...
Article ID:541 Firmware Upgrade on RV016, RV042, RV042G, and RV082 VPN
Routers Objective To upgrade the firmware, a specific file must be
downloaded from the Internet and uploaded to the device. Firmware
upgrades can fix software bugs, improve features, a...