Fail to sftp to Router/Switch for remote IOS/config upgrade

I have ssh2 enabled on a cisco3750 & 7204 running IOS 12.2 & 12.4 respectively both with "ip scp server enable" configured, the idea being to sftp configs & IOS down to them. I can open a V2 ssh session to each device no problem. When I attempt to use an sftp client (Putty/SecureFX) to do the file transfer the router/switch appears to authenticate OK but then the session is disconnected. I have logging & ssh/scp debug enabled on each cisco box and attempt to open the sftp connection. In each case the authentication (using same credentials as for SSH2 session) is successful but then the connection just closes. Can anyone help?


They don't make it real clear, but what you actually do is source from the router/switch. From the router/switch, you connect to a server that supports SCP and pull the IOS down or push the config to the server. You use the normal copy commands, but specify scp instead of tftp or ftp.
Hope that helps.