I'm trying to limit my date selection to 9/18/17 to 12/15/17

I've used the limit date feature and when that didn't work I had the date range to exclude by typing in the formula.

To limit the dates available in a date field, under the "Limits" tab, set the start and end date:

Here is how the filed would function with the above settings:

https://form.jotformpro.com/71274579152966

I thought I was limiting the dates they could register, I clicked on the link and can register for June dates. I only want a calendar that brings up Sept, Oct, Nov, Dec. How do I do this.
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You can open the calendar and view those dates but you cannot select them.  All the dates that are not in the range are greyed out and cannot be selected.  You can change the default date to the start date to have the calendar begin on that specific date:

Users would still be able to navigate through months/year not in the range.  They just won't be able to select any of those dates.