Duplicates checker - with messagebox listing duplicate results

Hi All,

I'm hoping to find a neat and professional looking solution to check and list duplicates in a message box giving the user the option to then go and delete as necessary.

The "remove duplicates" function in excel is great but doesn't list the account numbers it actually removed.

I'm therefore having to sort Column A (account code column) alphabetically and then manually check for duplicates.

Any help or links would be greatly appreciated