See what happens if you resize the field to be larger. Do you then see more of the checkboxes listed in the field?
I've read of cases where some developers put two or more copies of the same check box field on their layout. They gave one field a value list of some of the checkbox values and gave the other field a value list with the rest. Don't know if that is what you need to do here or not, but you can try that and see if it helps.
Thanks PhilModJunk. I did try re-sizing the field. The field got bigger, but it didn't change the number of checkboxes listed. It was a just a big field with the same number of checkboxes and a bunch of blank space. Is there an issue with compatability of layouts when publishing online? Or is there a limit to the number of checkboxes allowed in the online version?
Then please try my second suggestion. Define two value or more value lists, each with a subset of the total values you now have in one value list. Put several copies of the same field on your layout, but give each copy of the same field a checkbox format, but with a different value list. This will function identically to your original layout design, but may also work correctly when viewed viea a web browser.