I am having issues with using Custom Data Validation to limit the user input in the following way:
Tab 1 has a list (part of a table) on it with a number of text items, as well as 5 cells which are set to be equal to the user input from Tab 2. In Tab 2, I want to use custom data validation to prevent the user input from being equal to anything in the list in tab 1. I am currently trying to use =countif([list from tab 1],[user input from tab 2])<=1 as the formula but for some reason it isn't working. I know the formula is right because I tested it outside of data validation and it works. Does Custom Validation have a bug!?
Solved by D. D. in 28 mins