Unique items in combobox on userform

Hello everybody
I have in my attachment Data sheet ..
In range(I2:K2) I have validation lists based on worksheet change (Mr. Berlan has achieved that part perfectly)
Now I need to do the same idea exactly but in combo boxes in userform ..
That's I have list of items in combobox1 and when selecting an item , the combobox2 items should be depending on combo1 selected ..
the same with combobox3 depend on combobox2

Thanks sir for your help
When I loaded the form nothing populated in Combobox1 neither combobox2 ..
I got it ...
But Combobox1 should be first populated then combo2 then combo 3

Yes that's right
I tried to edit it by myself but i'm confused about the parameter in these lines

Private Sub ComboBox1_Click()
    Call cValues(ComboBox1.Value, ComboBox2, 2)
End Sub
Private Sub ComboBox2_Click()
    Call cValues(ComboBox2.Value, ComboBox3, 1)
End Sub

I think it is related to the column number of data i need to populate..but when trying to edit i got errors

Nice code MickG.

Obj.List = Dic.keys

Thanks a lot for this great solution.
It works like charm in your attachment .. When I copied the lines of code and use them in my attachment
I got an error "Permession denied" run time error 70

UserForm1.Show

Thanks a lot for this great solution.
It works like charm in your attachment .. When I copied the lines of code and use them in my attachment
I got an error "Permession denied" run time error 70

UserForm1.Show

Yes I removed RowSource in Combobox1 ..but still get the same error..
It's weird ..I exported your Userform and import it to my file and it is working well ...
I still need to know the cause of that weird problem

I restarted my pc and tested the file again and everything is perfect
Thanks a lot for your great and perfect solution you provided me.
Thank you very much

I restarted my pc and tested the file again and everything is perfect
Thanks a lot for your great and perfect solution you provided me.
Thank you very much