From Melissa Data Wiki
MAILERS+4 is an easy-to-use desktop program designed to help prepare a mailing for maximum postal discounts and efficient postal processing and delivery.
New Rates Notice
The new 2018 Rates do not go into effect until January 21, 2018. If you are not doing another mailing until after January 21, 2018 and wish to install the patch now, download the patch below. You will need to have Mailers+4 closed to run the patch.