After successfully uploading a directory from a local machine to a remote machine using the FTP session, I'm unable to open any other directory on the remote machine from the FTP

Explanation:  You can only upload a non-protected folder between the local and the remote machine. The folder you transferred is a protected folder. Because of this, the folder on the remote machine is empty, the File Transfer session is disabled, and you are unable to open any folders on the remotely managed workstation.

Action:  Do the following:

1. Delete the folder from the remote machine.

2. Disable the security settings on the protected folder.

3. Upload it to the remote machine again.