I also had the pniopcac.exe warning like in first post. I made some tests and could solve this by 2 ways.
First is switch-off virtual network adapter, as was mentioned earlier.
Second is switch-off "PROFINET IO RT-Protocol V2.0" protocol used by VPN-connection. Open properties of VPN-connection and deselect checkbox of following protocol:
PROFINET IO RT-Protocol V2.0
In my case this was sufficient.
There are also other Siemens protocols (used by VPN-connection) which also may be the cause of this warning:
SIMATIC Industrial Ethernet (ISO)
PROFINET IO RT-Protocol (LLDP)
you may try to switch-off them also.