Conditional Checkbox Selection/De-selection

I know this could most easily be accomplished through multiple questions on the form, but wanted to exhaust my options for an all-in-one solution.

Checkbox question with four answers with multi-select turned on:
All Three - Option 1 - Option 2 - Option 3

With All Three selected, how do I use the Update/Calculate Field to keep "All Three" selected, but de-select Options 1-3?
I have dollar amounts assigned to each option, and "All Three" is a discounted amount.
Again, this could be done with two questions, but it seems there should be a way to simplify it into a conditioned update. I'm just missing the way to deselect a checkbox programatically.

I found something that affects the check boxes, but it does not allow any selection even though the "All Three" option is not selected. It seems to completely dis-able the whole check box question. I'm just missing the way to control each option independently AND leave the check boxes alone when the condition is false.

The screenshot that you have uploaded will cause issues on your form because the setup is not right and could make issues not related only to those fields, but on other fields of your form as well.

Now looking at what you wrote above:

With All Three selected, how do I use the Update/Calculate Field to keep "All Three" selected, but de-select Options 1-3?

It sounds to me that you want to have the following:

Checkbox Options

 1. Option 1
 2. Option 2
 3. Option 3

If all 3 (Option 1, Option 2 and Option 3) are selected, Option 1 and Option 3 should seem as deselected, but still be counted as if they are selected?

At this time the conditions will not allow you to select or deselect the checkbox option, but I can not see exactly what you would like to accomplish.

Could you please describe us your use-case or scenario that you want to happen so that we can better understand what you are after and offer suggestions or alternatives.

What I have is:

Checkbox Options
1. All Three (#input_29_0 / Calculation value = 125)
2. Option 1 (#input_29_1 / Calculation value = 50)
3. Option 2 (#input_29_2 / Calculation value = 50)
4. Option 3 (#input_29_3 / Calculation value = 50)

My work-around is to list the "All Three" checkbox as a separate question and hide the Option 1-3 checkbox question when "All Three" checkbox question is filled. This allows a formula calculation field at the end of the form to ignore hidden fields and only add 125 for "All Three" if selected or total the individual options as checked. Still working on logic to prevent all three options being checked and a total of 150 instead of 125. That may just be a manual adjustment which is the case with a more complicated form.

Knowing that manipulating the input as shown will cause problems, I will use the work around. However, in the case of using checkboxes to calculate a grand total at the end of a form, being able to control the selection of individual options within a checkbox question would be highly valuable.

Thank you for the additional details.

Unfortunately the only way to accomplish the same, would be to separate the fields as you had mentioned earlier.

The only alternative that would be available is to grab the source code of your form and build this specific feature yourself or by hiring a developer.

You can see more about getting the source code of your form here: How to get the Full Source Code of your Form