Data Validation issue

[dkirk500]

I am new to this world, please bear with me. I have two sheets (Sheet 1 and Sheet 2), On column E of Sheet 2 , I have data that needs to prevent from duplications. So I used the data validation with countif formula on Sheet 2 (Col E) which works fine. However if I insert the data from Sheet 1 and linked to Sheet 2 column E (using vba cell referencing), it doesn't work anymore and it accepts the duplicate value. How my expectation can be achieved ? Any codes or other formulas?

Thanks,

 

[jasonb75]

using vba cell referencing

Are you sure that you're using vba and not a formula? The 2 are very different.

I think that we would need to see a visual example of the 2 sheets and the formula / vba that you are using to reference the cells in order to understand exactly what you're trying to achieve.