Script commands, such as msg <Hello, world!> must:
Parameters must have a "<" in front and a ">" at the end.
So, these forms are incorrect:
MSG <Hello, world!> msg<Hello, world!> MSG<Hello, world!> Msg <Hello, world!> msg <Hello, world!
This form is the only correct form:
msg <Hello, world!>
Leading spaces and tabs are insignificant, and are ignored by Quest.