I don't remember this specifically because it's been a while but did you finish the entire lesson? Sometimes there's errors in the lesson that I leave in there intentionally and they're fixed by the end of the lesson. If not let me know. As far as I can recall everything that's included in this lesson should be valid for any version of access.

Heather I think Richard, when he switched over the way the databases are stored in his server,  must have saved an "After the lesson" version / copy.  It used to be that you had to enter a password to open the database zip file.  Now that is taken care of at the web page level.  Times change.  (Keep in mind this course was produced in 2012 but it is still relevant today!)

I just opened my old copy up but it was with out the parameter and comparing it to a download I just did from the website.
The [Enter Date] is already in the Global Parameters up on the tool bar.
Mystery solved.

If you want to test this out, just back up 1 course to the Beginner 8 db.  That should be a clean db.
Or, even easier, just make the the parameter you enter into the query [My Date] instead of [Enter Date] that is in the video. So >=[My Date] And <[My Date]+1
Since [My Date] isn't in the Query Parameters it will error.  Now add in the [My Date] to the Query Parameters and the error will go away as in the video.
The key take away is - it isn't relevant what the parameter name is but how to fix it.

Thank you to you both.  
Richard, I had finished part 3 of lesson 9. I'm getting ready to do part 4.  I believe Scott is on to something though with his explanation about the parameter [Enter Date] already being declared.  (Please see below)  

Scott, you are right.  I did notice that the [Enter Date] parameter appeared to already be declared.  I did try to remove it and rerun the process but that didn't work.  I like your idea of using a different parameter name.  Thank you.  I'll give that a try just so I can see the process in action.  Again, thank you for taking the time to provide such a thorough answer.  

Heather -
Glad that helped.  I have been accused of being to wordy at times ;-)