Unchecky just saw Mailwasher Pro update as PUP. Mailwasher 7.12.53. I updated from within the program. Their site is https://www.firetrust.com/products/mailwasher-pro. Mailwasher is legit, a program of Firetrust in Australia or New Zealand, and has been around for a long time (I've been using it since 2008). I don't recall Unchecky throwing up an error message on it before.
(I don't understand how to use the info tool)
Customer support service by UserEcho