All those logs tell me is that it can't contact your backup server. If you can ping the backup location from the command line of your presence server, then open up a command line on your workstation and telnet to the backup server IP over port 22. (C:\> telnet <backup server ip> 22
If it won't work, it's likely that the SFTP client on your backup server isn't running or your network admin is blocking port 22. If you're using Microsoft IIS / FTP for backup, that won't work at all. IIS supports FTPS, not SFTP...and that little detail has been overlooked by many an admin, including yours truly.
If you need an SFTP client, try FTPd (free download).
If you have an SFTP client installed for backup, make sure:
a) The service is running (not stopped). Remember that the service can be running in services, but stopped on the SFTP client interface.
b) You have the backup service account and password entered into the SFTP client (no misspellings)
b) You have the correct directory listed for backup
c) The backup service account has at least Modify rights to the folder for backup
Most SFTP clients have logs, and looking at those should tell you what is happening.
Hope that helps.