The file upload feature does not function unless the following conditions are in place:
The feature must be enabled in the System Configuration dialog.
The workload where you intend to copy the files must have VNC console functionality.
The workload where you intend to copy the files must include a virtual CD-ROM as an integrated drive. the selected CD-ROM needs to be empty/ejected. If not empty, the user will get a message indicating they need to eject the existing media first.
The user executing the feature must be a valid, logged-in user.
The Application Server, the Orchestration Server, and the vSphere Server all need Write rights to the various locations where the files are copied (see Section 23.4, Stages of the File Upload), and each of these locations must have sufficient disk space to receive the files.