Data validation to prevent use of a character

It may seem strange to you, but I have my insanity, I mean, my reasons for this post.

I wish to prevent the use of the " ' " apostrophe in an entire column and I was wondering if this can be done with conditional formatting including a message of some type.

Hi Rick,

You can't use Conditional Formatting to prevent someone from using a character, but you can use Data Validation to do so.

For example, to prevent a user from using the apostrophe in cell A1, select that cell and open the Data Validation dialog. Select Custom and use the following formula:

=ISERROR(FIND("'",A1))

On the Error Alert tab, check the box for "Show error alert...", set the Style to Stop and then enter a custom message/title to show to the user when the validation is triggered because they typed an apostrophe.

Hope that helps!

What the heck?
I test your example in A1 and it works. I attempt to apply to column D and it doesnt work.
The only change I made to the formula was A1 to D:D
=ISERROR(FIND("'",D:D))
Is that not allowed?

It's not allowed to use FIND over an entire column. Instead, select column D and then set the formula to:

=ISERROR(FIND("'",D1))

Just like with formulas directly on the worksheet, this validation formula will change for every row selected. So if you look at the data validation formula for D820, it will show

=ISERROR(FIND("'",D820))

This should prevent them from typing an apostrophe in any cell in column D.

Lesson learned, thank you.