This article refers to SimCHAN v3-xx
When you start SimCHAN the Messages window at the bottom of the SimCHAN GUI may display Warning messages stating that one or more commands are 'invalid':-
The primary root cause is that SimCHAN has not been able to authenticate the installed licence file (lservrc.txt) located in the SimCHAN directory = C:\Program Files\Spirent Communications\SimCHAN. In this situation the GUI starts but the full operation of the software is prevented, i.e. it will refuse to acknowledge commands that are triggered by GUI settings / running a test. Another symptom of this issue that you should also notice in the Messages window is that it reports the software product as being "SimREPLAY" instead of the expected "SimCHAN" (see Figure 1) - please refer to article FAQ12511.
If the lservrc.txt licence file has been correctly authenticated then the Messages window should actually appear as follows, with no warnings:-
To resolve this please refer to advice provided in article SOL11089.