Oh by the way...

I was using the copy and flip along the red line to create the mirrored right side of the book case.
I did make sure the "Replace selection with component" box was checked in the component box.
I watched the video that was suggested by Dave R. It was very helpful.

Thanks again.

Thank you to all who have responded. Since I was in the first three steps of creating this drawing, I trashed it and started a new drawing. This time it worked perfectly. I know it is frustrating to not know exactly what the problem was, but I am just happy to be on my way. I am having fun again. I really appreciate you guys.

I have watched several how to videos on basic book shelf designing and I am unable to duplicate a very basic step.

1. create left side, tripple click to select it, make a component.
2. create right side, flip along red, tripple click to select it, make a component.
3. create a bottom shelf using rectangle between two sides, tripple click that shelf, make a component.

Step 3 never works out for me. Every time I tripple click the shelf it selects the two sides as well. It never does that on the videos.

I know I am going to light myself on fire when I see how simple this fix is, but...

What am I doing wrong??