Cheers jsprogg,

The script editor said I had some problem with nonmanifold geometry I didn't have a clue what that meant so I had a search around and found a YouTube video that gave examples. I'll include the link below so if anyone else out there is a noob like me they'll be pointed in the right direction. Using the clean up editor with the nonmanifold option checked helped me find where this error was occurring although it didn't fix the problem. It seemed the problem was where the cuffs joined the hands and arm. With a little bit of re-thinking I remodeled that area and everything is now fine.

Cheers again mate

Nonmanifold geometry
https://www.youtube.com/watch?v=Wa75X4QhIcQ