error “Gone No longer available”

I'm using Windows 8.1 and I have been using Windows Live Movie Maker and WonderShare video editing software for years to upload videos to YouTube with no problems. For the past three days when I try to upload any video I get this message: "Your movie wan't published because there was a net work problem. Please check you network connection, and then try again." Then under 'More information' is gives me this error message: "'My Movie.mp4' failed to upload to with the following error: "Gone No longer available". I have tried uploading one of my videos to YouTube at another person's house, no good, same error message. I had my ISP (CenturyLink) check my internet connection which is good. It's got to have something to do with my YouTube account because where ever I am, in different locations, it still gives me the same error message when I try to upload any video. Please help!! Thanks...