Here is the latest download for the DontTradeOnHolidays function. It is updated through the end of 2017 and includes New Years Day 2018. Download the ELD and Import it into Tradestation. It is an open code function called DontTradeOnHolidays.
The original blog post for the Don't Trade on Holidays for Tradestation is here:
It goes into great detail about this function to answer any questions you have. We keep the latest update for this function on this page link so make sure to bookmark this page for any holiday trading.