Data Validation - Omit Specific Value

Guan_Kwok 

Yes, you can ignore blank cells using the data validation drop-down feature in Excel. You can do this by selecting the cell you want to apply data validation to and then going to Data > Validation > Settings tab and ticking the “Ignore blank” checkbox.

To not show duplicates, you can use a formula-based approach.

Here’s how you can do it:

1. Select the cells you want to apply data validation to.
2. Go to the Data tab on the ribbon and click on Data Validation.
3. In the Data Validation dialog box, select List from the Allow drop-down list.
4. In the Source box, enter this formula: =IFERROR(INDEX($A$1:$A$10,MATCH(0,COUNTIF($B$1:B1,$A$1:$A$10),0)),””)
5. Click OK.

This formula will create a list of unique values from column A that you can use for data validation.

I hope this helps!