Hello & Welcome to JustAnswer.
Which version of Windows are you using?
Hold the windows key and press r to open run dialog
then in the run dialog type
and click ok
and then tell me what happens
Movie Maker can't start
May i remotely connect to your computer to troubleshoot the issue?
Click the link below and run the downloaded program
please click the downloaded file called support-logmeinrescue to open it and then run it