I have created a VPN connection in Windows using the New Network Connection wizard that comes with Windows.

It works without problems in most places, but there is one concrete place where, despite the connection to the remote public IP works fine, it is not able to validate the login/password and establish the VPN connection.

In this place, the network is 10.0.0.x (the same I use in other places where I am able to connect). The remote network is 192.168.x.x, so I suspect there is some kind of IP collision, because before connecting, a traceroute to i.e. 192.168.0.40 does not fail.

  1     4 ms     1 ms     1 ms  LINKSYS [10.0.0.1]
  2     5 ms     1 ms     1 ms  172.26.27.1
  3     4 ms     5 ms     3 ms  192.168.1.100
  ... (more)

I can't modify the local network further than the first router (10.0.0.1).

That is the only different I've found so far. Any idea about how to solve it? Thank you.