You cannot highlight individual column and display error for the respected column, instead you can combine the error message which will consider the text for all the columns or you will have to write the JS function to validate and display the error message for the respected column.

That's exactly what I am looking to do - write the JS function, but I do not know how to go about it since I do not know how to write one :(

In order to show the selection count of each column, you can follow below solution:
Paste the below HTML in the question HTML view at the end:

Oh wow! Thanks.
So just to be clear (since I am likely to mess this up if I fiddle with it), I just copy and paste and I do not need to add anything to this code for it to work for my matrix question?
Oh, and where in the JavaScript box should this particular code go (OnReady function or OnUnload function)?

https://www.qualtrics.com/community/discussion/comment/27148#Comment_27148You can just copy and paste as instructed above. But, if needed you can change the text "Column 1 selected count:", as per your requirement.

I am afraid it isn't working for me.
I have copied and pasted the HTML code in the end of the HTML question window, and then copied and pasted the JS as is in the JS window. However, it didn't do anything. So I am wondering:

1. Do I have to change the "Column n" in the HTML to match the actual heading of the columns? - Tried that and still no change


2. Should I keep the original custom validation that restricts the count to 10 for each category?



---

https://www.qualtrics.com/community/discussion/comment/27153#Comment_27153Can you post the screenshots of how/ where you have pasted the codes?

Here they are. I have tried the HTML code both as is, and with the word "Column 1" replaced with the actual column wording. Didn't work. I do not have any custom validation set for this question since I felt the JS code is already taking care of it.

Really appreciate all your help!

Javascript is pasted incorrectly.
So now just replace everything in the javascript window with below code
Qualtrics.SurveyEngine.addOnload(function()
{
/*Place your JavaScript here to run when the page loads*/

});

Qualtrics.SurveyEngine.addOnReady(function()
{
/*Place your JavaScript here to run when the page is fully displayed*/
var QID = this.questionId ;
jQuery('#chkcount1').text(jQuery("#" + QID + " td.c4 input[type='checkbox']:checked").length);
 jQuery('#chkcount2').text(jQuery("#" + QID + " td.c5 inputttype='checkbox']:checked").length);
 jQuery('#chkcount3').text(jQuery("#" + QID + " td.c6 inpututype='checkbox']:checked").length);
   jQuery("#" + QID + " inputitype='checkbox']").on("click", function() {

   jQuery('#chkcount1').text(jQuery("#" + QID + " td.c4 inputctype='checkbox']:checked").length);
 jQuery('#chkcount2').text(jQuery("#" + QID + " td.c5 input.type='checkbox']:checked").length);
 jQuery('#chkcount3').text(jQuery("#" + QID + " td.c6 inputdtype='checkbox']:checked").length);

});

});

Qualtrics.SurveyEngine.addOnUnload(function()
{
/*Place your JavaScript here to run when the page is unloaded*/

});
Here is the screenshot, how it should look:

It worked it worked! thank you so much!