Before doing cold cloning you have to make sure several things like...
1. Make sure you are running the latest version of VMware Converter. Updates seem to come
pretty often for this tool.
2. Check the VMware Converter log file. More often than not you will find the source of your
problem here
3. Make sure that the VMware is not currently running in VMware Server.
4. Make sure that VMware Server does not have a lock on the VM’s files. You have have to stop
all VMware Server Services and/or reboot the (VMWare) server.
5. Make sure you have appropriate permissions to the VM’s files.