Fabio,

If the object conditionally constructs then your WITH createobject() will throw an error. This code will not error:

myRef = createobject()
if ( vartype( m.myRef ) == "O" )
with m.myRef
endwith
endif


The previous code is correct only if vartype( m.myRef ) != "O"
is a aspected valid condition, otherwise it must fire a error.

This code can resolve this situation:

TRY
  WITH createobject()
  ENDWITH 
CATCH
ENDTRY