During the preflight checks, or when configuring a server in your DeployHQ project you may find one of the following errors are displayed when checking server connectivity:

```
SFTP channel could not be opened
```

```
could not start SFTP subsystem
```

This is most likely because SFTP hasn't been enabled on your server. You can check that the following line is uncommented and available in /etc/ssh/sshd_config:

```
Subsystem sftp /usr/lib/openssh/sftp-server
```

Please note that any changes to your config file will only take effect once you restart your SSH service.