Export to Excel functionality does not work on Unit conversion form because of hard-coded text columns (i.e. ‘*(‘, ‘/’, ‘)*’, ‘=’) on the grid for all the tabs.
This is the standard application issue and you can replicate this scenario by creating a sample form and add the data-source (e.g: CustTable) and grid control on the form and bound this grid from the data-source and also add the hard-coded text column to this grid and save this form. When you run this form and click the Export to excel option then error will occurred.
How to resolve
Simply change the hard-coded text column to the bound column and bound this column to display method and return the hard-coded text from there.