Date interpreted as text - how to force as number?

Hi

I have a cell, say $B$5, which contains a date, entered as a date and formatted as a date (dd/mm/yyyy).
By way of example I enter the string 23/03/2010 and it appears as 23/03/2010. Furthermore, if I undertake mathematical operations on this value it is treated, predictably and correctly, as having a numerical value 40260.
So far, so good.

Now, as part of a VBA macro there is the statement

Range($C$10).Value = Range($B$5).Value

Cell $C$10 is also formatted as a date, and on completion of the code, it displays the expected value 23/03/2010. Again, for mathematical operations treat this as having value 40260. EXCEPT IN ONE RESPECT: If I enter in another cell the formula
=ISNUMBER($C$10) it returns FALSE despite that =ISNUMBER($B$5) returns TRUE.

If I place the cursor on cell $C$10 and press <F2> to go into edit mode, followed by <Enter>, without making any changes, then subsequent query =ISNUMBER($C$10) returns TRUE.

What line of code can I enter after (or instead of) the above so that the query ISNUMBER($C$10) returns TRUE without requiring the user to edit the cell making no changes?

Thanks

You are quite right I was being very stupid