Seems like a lot of extra attractions and features in JV16 have a mind of their own. Duplicate file finder representing another one of those among many as posted in this forum.
However, as I did experience the same problem as you, I moved UP to "beyond Compare" that has proven to be an excellent program to compare files of all type, very fast and very accurate. Give it a shot and I do believe a free trial version is available.
Now, for disk wiping, as I experienced all sorts of problems with JV16, I moved UP to R-wipe and clean and that also has proven to be an irreplaceable software when it comes to functionality, reliability, and speed.
JV16 is in my arsenal just for cleaning the registry and that is all. I've been using the product since I believe mid 90's when it used to be completely free. Advanced System Care 3 does a great job too.
Good luck