workbook formulas stopped working

I've got a multi worksheet book analyzing monthly costs and sales for a restaurant. I entered the numbers for last month and the SUM function didn't work. The formula was already there, it just didn't tally the data. In other pages, same problem - according to the formulas in the blank cells, I should have data, but I don't. The only way I found to update the cells was to click inside the formula bar for each cell and press enter. Like I said, the formulas are already in place.
Furthermore, if I re-enter the formula and then drag the handle down to where I want my relative formulas, both the original value AND the relative formulas appear. Is this a virus or something??

Thanks for any help.

Hi there,

Not really sure, but it may be that calculation for the workbook has been switched to manual. To check (and change back to automatic if necessary) do the following four steps:

1. From the Tools menu select Options
2. From the Options dialog box, click the Calculation tab
3. Under the Calculation heading, ensure the Automatic radio button is selected
4. Click OK

If you want to leave manual calculation on, pressing F9 will calculate all the formulas in the workbook.

HTH

Robert

Originally Posted by Trebor76

Hi there,

Not really sure, but it may be that calculation for the workbook has been switched to manual. To check (and change back to automatic if necessary) do the following four steps:

1. From the Tools menu select Options
2. From the Options dialog box, click the Calculation tab
3. Under the Calculation heading, ensure the Automatic radio button is selected
4. Click OK

If you want to leave manual calculation on, pressing F9 will calculate all the formulas in the workbook.

HTH

Robert

Ahhhhhhhhhhh.................. There isn't a smiley icon to show this kind of relief. Thank you.