Error [516] after turning off VPN.

Symptoms

Without VPN the resolved IP is an external address, RDP connection via internet > works fine

• Connect to VPN

With VPN the IP of target server is changed, now its internal address, we work in LAN > works fine

• Disconnect VPN

After disconnecting from VPN IP address changes back to external one > unable to start published app, an error occurs:

• Issue resolves after reboot of PC or if you wait for a while (more than 1 hour)

Cause

Turning OFF VPN results to DNS Cache issue.

Resolution

Multiple connections shall be used as a workaround.

Create one with external IP and another one with internal. In this scenario, connection will work properly.