I think maybe it is timing out while waiting to connect, but when I manually launch the scheduled task (right click, run now) it correctly waits for the response from the server and transfers the files.
Because I can manually run the scheduled task I don't think it has anything to do with the key.
Here's the log
. 2007-11-06 02:30:00.605 --------------------------------------------------------------------------
. 2007-11-06 02:30:00.605 WinSCP Version 4.0.5 (Build 354) (OS 5.2.3790 Service Pack 1)
. 2007-11-06 02:30:00.605 Login time: Tuesday, November 06, 2007 2:30:00 AM
. 2007-11-06 02:30:00.605 --------------------------------------------------------------------------
. 2007-11-06 02:30:00.605 Session name: user@server.com
. 2007-11-06 02:30:00.605 Host name: ftp.server.com (Port: 22)
. 2007-11-06 02:30:00.605 User name: user (Password: Yes, Key file: No)
. 2007-11-06 02:30:00.605 Tunnel: No
. 2007-11-06 02:30:00.605 Transfer Protocol: SFTP (SCP)
. 2007-11-06 02:30:00.605 Ping type: -, Ping interval: 30 sec; Timeout: 15 sec
. 2007-11-06 02:30:00.605 Proxy: none
. 2007-11-06 02:30:00.605 SSH protocol version: 2; Compression: No
. 2007-11-06 02:30:00.605 Agent forwarding: No; TIS/CryptoCard: No; KI: Yes; GSSAPI: No
. 2007-11-06 02:30:00.605 Ciphers: aes,blowfish,3des,WARN,des; Ssh2DES: No
. 2007-11-06 02:30:00.605 SSH Bugs: -,-,-,-,-,-,-,-
. 2007-11-06 02:30:00.605 SFTP Bugs: -,-,-
. 2007-11-06 02:30:00.605 Return code variable: Autodetect; Lookup user groups: Yes
. 2007-11-06 02:30:00.605 Shell: default, EOL: 0
. 2007-11-06 02:30:00.605 Clear aliases: Yes, Unset nat.vars: Yes, Resolve symlinks: Yes
. 2007-11-06 02:30:00.605 Alias LS: No, Ign LS warn: Yes, Scp1 Comp: No
. 2007-11-06 02:30:00.605 Local directory: default, Remote directory: home, Update: No, Cache: Yes
. 2007-11-06 02:30:00.605 Cache directory changes: Yes, Permanent: Yes
. 2007-11-06 02:30:00.605 DST mode: 1
. 2007-11-06 02:30:00.605 --------------------------------------------------------------------------
. 2007-11-06 02:30:00.605 Looking up host "ftp.server.com"
. 2007-11-06 02:30:05.215 Connecting to xxx.xxx.xxx.xxx port 22
. 2007-11-06 02:30:20.356 Waiting for data timed out, asking user what to do.
. 2007-11-06 02:30:20.356 Asking user:
. 2007-11-06 02:30:20.356 Host has not answered for 15 seconds.
. 2007-11-06 02:30:20.356
. 2007-11-06 02:30:20.356 Wait for another 15 seconds? ()