You don't need the SUM function. Just use = A1*B1
In Basic terms I have created a macro that multiplys A1:B1 and shows the result in a cell, I want the MsgBox to show the result.
It's not clear if you are calculating within the macro, have a formula already in a cell or you are placing a formula into the cell via VBA.
However, this may be of help.
Calculate the product inside the code
Sub ShowCalc_Msg()
MsgBox Range("a1") * Range("B1")
End Sub
Reference values in cells A1:B1, write the result to C1, then display the value in a message box.
Sub ShowCalc_msg2()
Range("C1") = Range("A1") * Range("B1")
MsgBox Range("C1")
End Sub
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