windows movie maker not playing my file i just created

Hi there, I am in a bit of a pickle and really do not know much about computers.  I have been working on a project for the past month for our family, finally finished last night and saved it at 12:18 am.  At 6 am I tried to open and received a message that said the file was not compatible or may be corrupt.  I am completely lost.  I have uploaded to Skydrive and made it public.  I have tried to repair Essentials 11, nothing, so I uninstalled and tried to reinstall (told me I had to use Essentials 12.  Still nothing.  I have copies on my external hard drive I even made a test DVD....but I cannot open any of them.  (accept the DVD is fine, but not done)  Thank you all so very much for any advise.