Thanks maroon,

The bad command was an after thought, and I already use debug while investgating my code.
In general, the no-such-identifier message shows the line number

Cant say that I have seen that happen, but it could have slipped my mind.

but there are exceptions, such as when the bad identifier is in the label or command on the popups menu.

Nope, I checked, not in labels or commands. Are there any other exceptions ?