In older SonicOS releases there was the option “Enable Windows Networking (NetBios) BroadCast” in the WAN GroupVPN available. However, this option was removed from 188.8.131.52 as the configuration is now entirely moved in the IP Helper Policies. Previously, even after enabling the option in the Advanced Settings of the VPN, you had to enable and configure the IP Helper Policies to make this feature working.
As the option 'Enable Windows Networking (NetBIOS) Broadcast' is only used to add IP Helper policies, in our latest releases this option is removed from the Advanced tab of VPN policies. If you still need this feature, you should add IP helper policies manually.
To do that, follow the steps below:
Go to Network | IPHelper, under IP Helper settings, select the checkbox next to Enable IP Helper.
Under Relay Protocols, select the Enable checkbox of NetBIOS. Click Accept button at the top left to save the configuration.
Under Policies, click Add button:
Add IP Helper Policy window will display.
Select the checkbox next to Enable policy
Choose NetBIOS from the Protocol drop-down list
Select the appropriate source and destination in the From/To drop-down list.
NOTE: You need create another reflexive policy with From/To filed interchanged to make sure NetBIOS works correctly.