This name suffix is enabled for routing to the forest: %1. Therefore, Windows routes all authentication requests that use ...

This name suffix is enabled for routing to the forest: %1. Therefore, Windows routes all authentication requests that use this name to that forest.  To route the authentication requests to the forest: %2, disable routing to the name suffix for the %1 forest.  Would you like to open the Name Suffix Routing tab for the %1 forest trust where you can disable routing for this name suffix now?