I was looking for a video for knowledge and blogpost which I found on YouTube under Standard YouTube License. However, when I tried to contact the owner, I think he/she is not active on YouTube anymore. Because that is the last video uploaded by the user and that is 7 years ago. What to do?
Nothing, really. YouTube Standard License doesn't give you any rights to redistribute or remix the video (see my answer here). You can only try to contact the uploader through other means. Look through their channel info to see if you can find a website, Twitter, E-Mail address or any other contact information. Depending on how badly you want to use this video, there are also other means of
online stalking finding contact information that you might try. For example, if he uses a distinct user name you can try to search for that user name on Google, Twitter or other social media and see if you find something.