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Hi,

I need some help understand how validation works and I don't/can't hace admin right, so any script solution won't work.
So here is my problem. I hace an array (number) displayed as checkboxees, and I would like that users can't have chaeck a specific column with anu other (so exclusive behaviour for this particular column). As I can't use a script, I think the best practice would be to use validation. However, I have tried numerus attempts (using count, sums etc.) and none of them seems to work. Do you have any sugestions on what I should enter in the validation field to prevent users to both check that specific column with any of the other 3?