How can I solve this problem?
There could be multiple causes to this issue:
The driver isn't installed properly which means you will have to use the support CD or the driver for the capture card to install it. In most of the cases, this is the common error.
The driver is not compatible with the operating system where the device is attached to.
You have multiple video capture devices installed, and the software you use is not configured properly. Access its Settings menu, then choose the correct capture device.