To enable the ssh at ESXi server, at the server console, press ALT-F1, type "unsupported", press Enter. When the password prompt shows up, enter the root password to log in.
Delete the first character # in the line containing ssh in the file /etc/inetd.conf to make it similar to the line below, then reboot the server.
ssh stream tcp nowait root /sbin/dropbearmulti dropbear ...
After ssh is enabled, putty can ssh to the server from your PC. WinSCP can upload/download files with the server as well.
An other tool can download files from the server is Firefox. Following example URL can browse the files at datastore1 on the server that has the IP address as 192.168.111.222:
In addition, the ESXi server's datastore browser also can upload and download files between the server and your PC.