I want to create a combo box and I have entered the list of values by fillinmg in the range in ListFillRange, say D1:D5. Howebver, among the values in D1 to D5, there are some duplicate. Can we have a combox box without any duplicate value?

For example, if the values of D1, D2, D3, D4, D5 are a, b, c, b, a

I would like to have a combo box showing only 3 values, namely a, b, c. But now I have the value a, b, c, b, a.

Can anyone help? Thx