Hi, there.
Very strange. Normally, if you say something into the mic and the speech engine is raising events, you'll get some sort of feedback as to whether the command is recognized or not. Are you using any of the alternate speech engines by chance? These are the ones that are not built in and require separate installation:
http://voiceattack.com/alternate The reason I ask is that those speech engines do not provide an, 'unrecognized' event (and unrecognized commands would not show up in the log). Also, have you tried the default profile that comes with VoiceAttack? This is the profile that has, 'calculator', 'notepad', 'wordpad' and some others. Just wondering if you had any luck with that profile.
If the speech engine you are using is somehow not yielding speech events (recognized/unrecognized), it's possible there could be something up on your system. You'll want to first try a system scan to see if that resolves anything simple:
https://support.microsoft.com/en-us/help/4026529/windows-10-using-system-file-checker This is good to run from time to time (even if you don't suspect problems).
Next, you'll want to take a look at this thread, as it's helped many over the years with mysterious speech engine issues:
https://forum.voiceattack.com/smf/index.php?topic=64.0 Hope that helps!