1 IS AN EXAMPLE, ASSUME COLUMN A IS ON SHEET 1 AND COLUMN B IS ON SHEET 2
1 1
2 2
3 3
4 4
5
6 6
7
8 8
9 9
10 10

2 in the userform1 , in the list box appears all the numbers, but I need Appears the Number 5 and 7, they are the only unduplicated numbers