Custom ribbon button will not check checkboxes

I have a custom ribbon with checboxes that will show/hide sheets. I have added a button that will show all three sheets. I would like the button to set all three checkboxes to true as well. Thanks!

You need to set up an onLoad hook in your custom XML for the workbook so that you can store a reference to the Ribbon. Then your macro can invalidate the ribbon after changing the sheet visibility so the checkboxes will fire their callbacks and reset their checked states. See attached.

PS When your questions are solved, as I assume your last one is, please mark them accordingly.