When I convert videos using RZ Video Converter, "RZ soft trial version" is written on the video. How to remove it?
That message appears because you actually have the trial version of the software. To remove the message, the software needs to be purchased from the developer's website. What you have installed is a trial version that has limitations (eg. watermark on videos).
Buy the application: http://www.rzvideoconverter.com/rzvideoconverter/videoconverterpurchase.html
Once you have purchased it, a serial number will be issued to you to register it, then the watermark won't appear on your videos any more.
If you want to remove watermarks or logo from a video converter, no doubt, you need a registration code. I always use Aunsoft Video Converter, which wonderfully convert Christmas movies, interesting videos, photo videos, and etc.
Hope it works out!