How can I identify the specific error causing the need for 'rumus if error 0' in my spreadsheet?

Use the error checking tools within your spreadsheet software. Excel and Google Sheets will often provide a description of the error when you select the cell. Common errors include #DIV/0! (division by zero), #VALUE! (incorrect data type), and #REF! (invalid cell reference). Understanding the error message is the first step to fixing the underlying problem.