Does anybody know a VBA code that will check Cloumn R values against Column BV values? And if any cell in the same row in column R is greater than the cell in the same row in column BV then produce a pop up warning saying they don't have enough inventory.

The cells in the cloumn R and BV are a result of a formula that is a sum and the user will manually type in the cells that the formula will read from.

Please help.

windows XP
excel 2003