I'm sorry to hear that you're having trouble with Excel 2007. Let's see if we can figure out what's going on.

First, make sure that the cells you're trying to multiply are formatted as numbers. To do this, select the cells and go to the Home tab in the ribbon. In the Number section, make sure that "General" is selected. If it's not, click on the drop-down arrow and select "General".

If the cells are already formatted as numbers, try typing the formula again, but this time, make sure that you're typing it correctly. The formula you should be using is "=C3*D3" (without the quotes). Make sure that you're typing the equal sign at the beginning of the formula, and that you're using the asterisk (*) symbol for multiplication.

If that still doesn't work, try using the formula bar to enter the formula instead of typing it directly into the cell. To do this, click on the cell where you want the product to appear (in this case, E3), and then click on the formula bar at the top of the screen. Type the formula "=C3*D3" into the formula bar, and then press Enter.

If none of these solutions work, it's possible that there's an issue with your installation of Excel 2007. You may want to try repairing or reinstalling the program to see if that resolves the issue.

1. Select the cells and go to the Home tab in the ribbon.
2. In the Number section, make sure that "General" is selected.
3. If it's not, click on the drop-down arrow and select "General".
4. Try typing the formula again, but this time, make sure that you're typing it correctly.
5. The formula you should be using is "=C3*D3" (without the quotes).
6. Make sure that you're typing the equal sign at the beginning of the formula, and that you're using the asterisk (*) symbol for multiplication.
7. Try using the formula bar to enter the formula instead of typing it directly into the cell.
8. Click on the cell where you want the product to appear (in this case, E3), and then click on the formula bar at the top of the screen.
9. Type the formula "=C3*D3" into the formula bar, and then press Enter.