Simcenter STAR-CCM+ Why is my surface wrapper running in serial mode?

When you are using the surface wrapper, sometimes it might seem that it is running is serial even though it has been set to parallel run. Or you might see a warning in the output window as - 

Warning: "using legacy wrapper"

This can happen for geometries which are using specific features such as partial wrapping or local surface wrapping which are not compatible with parallel wrapping. In such cases, the solver will default to legacy wrapping and hence will take longer. 

However, if you don't have any of these specific features and your surface wrapper still seems to be very slow i.e. running is serial mode, then check the properties settings of surface wrapper for the below. 

In the Expert settings of Properties window of Surface wrapper, you will see this option of Legacy wrapper. By default, it is activated.
Untick this box and this should force the surface wrapper to run in parallel.