Then you would need to import the disks into ESX. See below.
So say you want to migrate a VM guest from an old GSX or Workstation installation to ESX3 and that guest is not Windows so using the live converter is not an option or is not available if it is a Windows guest. There should be *.vmdk files associated with the GSX /Workstation based guest. One of these files is a disk descriptor file and is pretty small this contains information about the disk itself, then there are the actual storage vmdk files. Naming conventions would look similar to his for a roughly 3.5GB disk. There could be more depending on size and number of virtual disks associated with the VM.
disk1.vmdk 1KB
disk1-f001.vmdk 2,000,000KB
disk1-f002.vmdk 1,500,000KB
In this case you would power down the VM and using your preferred method SCP the files to an ESX host. Now you need to properly import the disks so ESX understands what they are since the ESX file system is different (VMFS3). The command must be run with root privileges, "vmkfstools -i " then point to the path of the descriptor disk file put a space and then the location where you want the imported disk on a vmfs partition. The x's here represent the numbers associated with your hba, target, lun, etc.
vmkfstools -i /path/disk1.vmdk /vmfs/volumes/vmhbax:x:xlunxx/newvm/disk1.vmdk
Once complete use the Virtual Infrastructure client to create a new VM of the same OS type and to use an existing disk. Browse to that disk complete the wizard and hopefully everything boots as expected.
