Sometimes the Copy function is not available, and you will get an error if you use it in VBA.  In form view, the Copy button is greyed out on the ribbon if nothing can be copied (see picture below).  Only when there is a selected object (form, query, etc. on the navigation pane) or highlighted text can you use Copy.

Garry's actually meaning the 'Copy' Button on the Calculator form.

Kevin Robertson is correct. I mean on Calculator 7 lesson.

Does it work in the database Richard built in the videos?
Download the sample database and compare what Richard did with your own.

Kevin, I am not a cold member

But the line "DoCmd.RunCommand acCmdCopy" does rely on the Copy button on the Access ribbon being active, otherwise it returns the error you saw.  You can do a test.  Set the form's default view to "single form."  Open the form, and see whether the Access ribbon's Copy button is greyed out or not when the error occurs.

I usually avoid using "DoCmd.RunCommand acCmdCopy", because it could generate a run-time error -- while pressing Ctrl-C doesn't (SendKeys "^c").