Cell Being Evaluated Contains a Constant

Hello,

I know enough about excel to be dangerous. The issue I have is I have created a worksheet that references another workbook and worksheet. It has been working fine until now. I had to insert a new row and copy the formula from the cell above down to the cell in the new row. This works fine until I need to change the referenced cell i.e. "sheet1!A1" to "sheet1!A4". I hit F2 to edit the cell number, I change A1 to A4 hit enter and instead of it referencing the information from the "sheet1!A4". The formula shows up. So I went to Tools then Formula Auditing then Evaluate Formula it tells me that "The Cell Currently Being Evaluated Contains a Constant"

Like I said I know enough about Excel to screw things up. I would appreciate your help

Is there an equal sign at the beginning of the statement?

Yes - the is a "=" sign at the beginning. The formula works until I change the cell reference.