vCenter Convert has the option to pre-upload the helper iso image on a datastore. In such cases the helper ISO image is not deployed by Converter server but is directly attached from that datastore. The switch is 'helperIsoDatastoreDirectory'. This setting is for using the helper ISO image from a datastore instead of attaching it by Converter server. If unset or empty, the regular mechanism for attaching a local ISO by Converter server will be used. This issue might occur only when converting powered on Linux machines.
On the machine where Converter Standalone server runs, locate the converter-worker.xml file in the "\%ALLUSERSPROFILE%\Application Data\VMware\VMware Converter Standalone" folder.
Open the converter-worker.xml file in a text editor and replace the default value for 'helperIsoDatastoreDirectory'.
Note: The value is the directory, including the datastore name, where the ISO images are located. The name of the image must be the same as the local image, for example 'converter-helper-vm.iso".
Example: If the ISO image is located at "[datastore] dir1/dir2/converter-helper-vm.iso", add the "[datastore] dir1/dir2" value for 'helperIsoDatastoreDirectory'. This datastore must be accessible by the host which will run the helper Virtual Machine.
In the Services section of the Microsoft Management Console, restart the Converter Standalone Worker service.
Alternatively, reboot the system.