In a particular strange workbook,
In cell A1, I key the value 0
In cell A2, I key the formula =IF(A1="APPLE", 1, 0)
The result in cell A2 gives 1.
I tried to replicate the same in a new workbook, I get 0 in both cells. What happened to the strange workbook? I may seem like I am lying, but it's true. Included below is screen shot but in different cells.

EDIT: Cell A2 (G212) will show 1 when A1 (G211) is 0, empty or case-insensitive Apple e.g. aPpLe, ApPlE etc.

"APPLE"? How is the cell formatted? Could you post a screenshot with the edit focus on G211? – Matteo Aug 13 '12 at 9:17