Making the Duplicate Checking case sensitive?

Hey guys. I want to run Conditional Formatting to highlight all duplicates in a list of ID codes.
Problem is, some of the ID's in the list are the same except for the last letting being either in lower or upper case.
Is there any way to get excel to run the duplicate check but only highlight duplicates if the are EXACTLY the same in terms of letters AND case?!

Hi,
Pls follow the below.........

In 2007:
1. Highlight all the cells on the rows you want formatted, here assumed to
be A8:A13.
2. Choose Home, Conditional Formatting, New Rule
3. Choose Use a formula to determine which cell to format
4. In the Format values where this formula is true enter the following
formula:
=SUMPRODUCT(--EXACT(A$8:A$13,A8))>1
5. Click the Format button and choose a format.
6. Click OK twice
--
If this helps, please click the Yes button.

Originally Posted by rishikrsaw

Hi,
Pls follow the below.........

In 2007:
1. Highlight all the cells on the rows you want formatted, here assumed to
be A8:A13.
2. Choose Home, Conditional Formatting, New Rule
3. Choose Use a formula to determine which cell to format
4. In the Format values where this formula is true enter the following
formula:
=SUMPRODUCT(--EXACT(A$8:A$13,A8))>1
5. Click the Format button and choose a format.
6. Click OK twice
--
If this helps, please click the Yes button.

Thanks a lot!!