DLO Cannot Connect to NDL over VPN

Hello,

I am using DLO 7.6 on Server 2012 R2.

I have a DLO server in my data center which is running all roles.

If I am connected to the corporate network my DLO client can connect and backup data to my Network User Data Folder  on the DLO server. However, when I connect to the network by VPN I cannot connect. I immediately get the following popup:

If I used Windows Explorer I get an error when I try to connect to the Network User Data Folder:

However, if my laptop is connected to the corporate network I can browse the Network User Data Folder.

There are no errors from what I can see in the logs what are related to this issue.

Any ideas on why I cannot authenticate and get permission while connecting by VPN.

Kind regards,

Cameron