The file name you try to open might contain symbols that can not be interpreted by Movavi software.
We would recommend to rename file. If the problem remains:
- Make sure the file is not opened in any other application.
- Make sure that output folder is located on the hard drive as Movavi software can not save directly to CD/DVD disks or connected devices.
- If the input file is located on external hard-drive or flash-drive, make sure the device is properly connected to your computer and does not disconnect mid-conversion, try also plugging the device into another port.