It really depends what exactly is the problem in your case. Here are some articles that might help you figure out what the problem is and possibly how to resolve it but call support if you have it, it can be tricky. If it is saying file not found the vmdk descriptor file may need to be recreated. Figuring out why SVmotion failed (is a datastore low on space) would also be important to figure out.

There is a good website to help create vmdk files, kudos to whoever wrote this:

http://kb.vmware.com/kb/1003743

Hope that helps

Hanna