Are you sure you're doing it right?
Login the remote box through ssh or whatever you want.
Use screen to run an application:
Prest Ctrl-A and then D
You'll be return to the shell
Logout of the remote box.
Login again and run
You will see the vi editor.
should tell you if there are any other screen sessions running. In that case you should use:
screen -r pid.tty.host
using the "pid.tty.host" from the previous command.