On the machine running Converter, go to: %ALLUSERSPROFILE%\VMware\VMware vCenter Converter Standalone\logs .
Try the conversion wizard again.
VMware Converter often fails to negotiate encryption with modern SSH defaults. Scroll to the bottom of the file or find the Ciphers and MACs sections. You may need to add or uncomment these lines to allow older, less secure algorithms that Converter supports: On the machine running Converter
Manually clean up on the source Linux:
Troubleshooting VMware Converter: "Unable to Query the Live Linux Source Machine" On the machine running Converter