you must download a iku2.1-setup.exe This software is the youku produced. After installation, you can watch and download. good luck.

You must download a software of Video Transcode on your computer at first, like Total Video Converter, Iku, 格式工厂, etc. and then you can transcoding it(the video you had downloaded) to MP4 format or other format you wanted with the software of Video Transcode. My English is not good, Hope you can understand what I am saying.

I would recommend using VideoHunt Free Online Video Downloader. It's a web-based tool, and it's free. I did not encounter some technical problems so far, you guys can try it as well.

I use NoteBurner YouTube Video Downloader - works very well. Most importantly, it is a totally freeware.

You may get the Allavssoft and a step by step guide on how to download online video and music files to any video or audio format at https://www.allavsoft.com