Populate combo box with unique values only

Hi All,


I have a worksheet which has a combobox and i am populating with the sheet2 values(assume column c values).

this works fine.
But........... sheet2's coulmn c contains 50 values with repeated values in it.

I want my combo box to contain unique values only.

example:
sheet2 column c

1. john
2. Harry
3. John
4. Petter
5. Harry
6. Petter
7. petter
.
.
.
.


1. Now i want my combox to contain only
john
harry
petter

(only 3 names)

2. Is it possible to populate with out using VBA code?

Please help me out.