A workaround that may fix all issues you encounter.

Related software: WonderFox DVD Ripper Pro, WonderFox Free DVD Ripper, WonderFox DVD Video Converter.

First, convert the DVD to an ISO image.

1. Insert a DVD into the DVD drive and load the DVD in the software.
2. Click the "Output format" area on the right to expand the format-selection list.
3. Find the "1:1 Quick Copy" option in the second column on the left and choose ISO as the output format.
4. Click "RUN" at the bottom to make an ISO image of the DVD.

Second, relaunch the software and import the ISO image, then convert it to MP4 or other formats.

5. Click "ISO Image" on the main interface, then you can browse your computer and choose the ISO file you just made.
6. Click the "Output format" area on the right and choose an output format, such as MP4, AVI, MKV, etc.
7. Click "RUN" at the bottom to start ripping.

Note: the created ISO should be about the same size as the DVD. Before ripping the ISO, please check its size first. If its size is much smaller and does not play in VLC or other programs, the ISO may be incomplete and cannot be used. In this case, please select the DVD folder option next to the ISO option and see if it works.