Combobox refresh

I have a spreadsheet with 2 comboboxes on it. The listfillrange of the second combobox depends on the value in the first combobox but when I select a value from the first combobox then click and choose a value from the second combobox, I get cells on my spreadsheet that will not calculate. If I click on the second combobox a second time and choose the same item again, then all is well. It is almost as if excel has to refresh in order for the listfillrange to change in the second combobox. Is this the problem?

Can you post the code so we can get a better understanding of what is happening?

Have you verified what the data type is before performing the calculation in debug mode?