I'm using Excel 2003. We have a very complex spreadhseet that has been used by our company for years. When I open up one of these spreadsheets, if I click on a cell to check or edit the formula, and then press enter to get the updated value/solution, the solution goes to zero, whn that is clearly not the correct answer to the calculation. It seems to only happen in formulas that reference other cells. (ie. If i simply type in 1000/25, instead of A3/C21, it renders out the correct answer to the formula). I have checked that the cells are formatted to General or Number and this doesn't solve the problem). I have checked error checking settings and this doesn't seem to be it. I will say though that if I click in the formula bar and hit F9, the correct answer suddenly appears. However, now I've lost my formula, so that obviously doesn't work as a long term solution. Has anyone ever seen anything like this?? Any help would be much appreciated!! Thank you.