There is known issue with SpeechExec V11 when a user has been taking advantage of the free trial through SpeechLive and then attempts to utilise a product/license key to activate the software. 

As you can see, the option is not available and there is nowhere to enter the key. 

You will need to exit out of the software before completing the following:

Go to the file explorer in the PC.

Navigate to %Appdata% within the file explorer on the PC by entering "%Appdata%" into the search bar.

Access the 'Philips Speech' folder...

Then, locate and open the 'SpeechExec' folder...

Now, locate and delete the users .XML file which should be labeled with the users name...

Exit the file explorer and open up the SpeechExec software again where you will now be able to register with a product key.