Hi,

I need help with data validation.

I understand the basics of data validation but need help using
formulas to allow user to choose YES as option.

I have three columns ABC and right now I have them with data
validation as list with two options YES and NO.

I need to change it to do this:

In cell D1 there is a code that changes how the columns interact with
each other:

Any column can have NO regardless it’s the YES that has conditions.

If cell D1 contains:

1 - only one of the columns can have YES (ie A - Yes, B and C would
have NO).
3 - Any column can have YES
5 - Either column A or column B can have Yes but not both, it doesn
matter for column C
7 - Either column A or column C can have Yes but not both, it doesn't
matter for column B
9 - Either column B or Column C can have Yes but not both, it doesn’t
matter for column A

Of course I want an in cell drop down with the options for YES or NO
the same way as I have it right now as a LIST.
How can I use this in Data validation?
Thanks so much for any help.

I have a user form that will control this, but the user has the chance
to go directly to the sheet and make changes/select it.

Cheers.