If you will look at this image:

The blue numbers represent the tab index property that I have for the controls. My problem is that when I put the focus on the first textbox control and start hitting TAB it goes from index 0 to 1 to 5 and skips the three controls that are in the group box.
How can I set this up so that when I put the focus on the first text box (index 0) and continue to TAB it will cycle straight from controls 0 to 5 without skipping over the controls in the group box?
In Visual Studio open your windows forms designer. Go to menu ‘View’ and then use ‘Tab Order’.
Here you will see the tree-like control order.
Just click the controls in the order you want to have.