Hi Racing,
If you are currently using ActiveX comboboxes from the Controls Toolbar to provide your in-cell dropdown, I suggest that you switch to using cell Data > Validation with a List instead. This provides a dropdown which automatically sizes with the cell, is very easy to use and set up, and requires much less memory than a combobox control. To use validation to get an in-cell dropdown, simply select the cell or cells, go to Data > Validation > select List in the Allow dropdown, and in the Source refedit box either type your list separated by commas, or enter a referenct to a range of cells that contains your list.