Problem with Matlab Interface with STK

Hi everyone, I am trying to get a Matlab interface with Systems Tool Kit (STK) by COM, but when I run this command:

app = actxserver('STK11.Application')

I Get this response:

Error using feval
Server Creation Failed: Error en la ejecución de servidor

Error in actxserver (line 86)
h=feval(['COM.' convertedProgID], 'server', machinename, interface);

I have seen that some others have the same problem with others applications, but I have't found a solution for mine. Does anybody have an advice for me?