Hello Danerida

No, I always clear all the data before running the macro again. And you can see that I use the ".Validation.Delete" method before selecting the range in column G.

In the meantime I solved the issue.

It was due to the default value I insert in each cell in column F ("Selezioni...") before creating the data validation list in column G. This value doesn't exist in the first drop-down list so I got an error. Instead, if I initialize the value of each cell in column F with "LIV" or any existing value in the first drop-down list ("MLV", "ARR",...), it works.

Thanks anyway