Probably Nero will not assign the default Video format (NTSC or PAL) to its setting while installing Nero (Vision) in Windows Vista. We should set the video format after installing by manually as follows.
Start Nero Vision Expand the "More" button which is in the bottom of the Nero Vision Window. Click on the "Default Video Options" and it will pop another window which contains several options and settings. Since we have to add the video format, just select the "General" tab. From the dropdown menu under "Video Mode" Select either NTSC or PAL as Video mode.
If you confused which format to select, just scroll down and select your country name and Nero will automatically assign the format related your country. Leave remain settings as it is and hit OK to save the setting.
Now, try to add video and audio files to your projects and it will add it and will not show any error message.
Note: For some kind of Video files (*.avi, *.divx, *.xvid, *.vob etc) required Codec to add, run and burn the video files. Get the All In One Codec pack from the following location for absolutely free and install it before you start your video project.
http://www.free-codecs.com/download/K_lite_codec_pack.htm (K-Lite Codec Pack for all kind of codec)
http://www.xpcodecpack.com/download (XP Codec Pack - May also works in Vista too. Media Player Classic also supplied with this pack for free to run DVD files)
http://www.free-codecs.com/download/vista_codec_package.htm (Vista Codec Pack - Especially for Vista Users)
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