Highlight top duplicate cell

Hi,
I need help finding duplicate cells. In xls file I have two table (Table 1, Table2), both table has same columns ID1 and ID2. In Table 2 I have unique records in both columns and I need to find duplicate values in Table1 and only to higlight the top unique cell in column ID1. In attached file I manually highlighted 3 cells but I need to higlight in whole column ID1 based on a unique cell in Table 2 column ID1. Thank you