When creating a .CSV file, these sheets automatically remove leading zero's after you input them into the cell and press enter. This is often a problem for the UPC column. We'll show you how to correct this below:
As you can see there are no leading zeros for the UPC column.
To fix this you can click on the column letter which will select the whole column.
Then you can click on Format in the Toolbar>Cells/Column>In the Numbers tab under Category Select Text>OK.
You will then be able to type leading zero's and they will stay.