When you click the Troubleshoot Camera button in Program Setup / Capture, you will see the window above. This window will allow you to install or reinstall codecs that are needed for your camera.
What are codecs? Codec stands for compressor and decompressor. These are needed to capture and play videos. As there are many different kinds of videos out there, there are also many codecs needed to play them.
This list of codecs included here will cover most cameras and video types.
TIP: Sometimes when something goes wrong during capture or import (such as trying to import a corrupt file), the codec being used becomes corrupt. Reinstalling it will fix the problem.
TIP: If you use this utility to install a codec and the codec is already installed, the utility may uninstall the codec. Watch for this and simply rerun the installer to install again.