Even with a "serial," the software may fail to activate or get stuck in an endless restart loop .
Since Movie Studio 11 is over a decade old, modern free video editors often outperform it and support newer file formats (like 4K and HEVC): sony-vegas-movie-studio-11-hd-platinum-serial-number-free
A professional-grade editor with a very powerful free version. Even with a "serial," the software may fail