Error 421 Connection timed-out
From BulletProof Wiki
This usually means that the server closed the control connection because it didn't receive any information from the client within your server timeout length.
First verify that your security and firewall settings are setup correctly.
Then make sure to set your server to allow 'noop' commands in both the user and group account settings.
- setup --> user accounts --> miscellaneous --> commands
- setup --> group accounts --> miscellaneous --> commands
Finally, you will also need to adjust your time out length in both the user and group account settings.
- setup --> user accounts --> miscellaneous --> misc setup
- setup --> group accounts --> miscellaneous --> misc setup

