ViewerX supports file transfer with all versions of UltraVNC and TightVNC up to v1.2 (support for TightVNC v2.0 is planned).
ServerX doesn't support file transfer by design. It would be a huge security hole to have a COM component that allows file-transfer to a remote computer.
If you have to have file-transfer in ServerX, we could discuss it and perhaps this feature could be implemented as a custom programming project for a fee.
Kindest Regards,SmartCode Solutions Support