final cut pro wont play after export

Hi

So I have made a wee movie using pictures, video clips and music. All good and plays well in Final Cut Pro..... HOWEVER...…. I have exported to windows machine and will not play at all

Says error, corrupt, etc

Tried converting to /WAV - MP4 - MOV

Nothing works but plays ok on my MacBook

Most frustrating as it a video for work activities and is required

Any ideas or suggestions how to resolve this most frustrating issue will be most apricated

Thank You