When using -hostkey option in script mode, open command fails with "Too many parameters" error.

I cannot use the -hostkey option with the open command in a script.

When I try like this:

winscp.com /command "open sftp//username/password@ipaddress -hostkey ""ssh-rsa 1536 XX:XX:XX:XX:XX:XX:XX:XX:XX""" "get xxx" exit

I get the following error:

Too many parameters for command 'open'

I get the same error when I tried rearranging and placing the -hostkey option first, like this.

winscp.com /command "open -hostkey ""ssh-rsa 1536 XX:XX:XX:XX:XX:XX:XX:XX:XX"" sftp//username/password@ipaddress" "get xxx" exit

The exact same command like works without the -hostkey value, but only from my interactive session where I have the key stored. However, I need this to work from an automatically scheduled SSIS job, and it always fails to accept the key from the SFTP site since it runs from the SQLServerAGENT user.

In my post, I accidentally omitted the colon (:) after the sftp in both examples, but the actual script does contain the proper format.

winscp.com /command "open sftp://username/password@ipaddress -hostkey ""ssh-rsa 1536 XX:XX:XX:XX:XX:XX:XX:XX:XX""" "get xxx" exit
winscp.com /command "open -hostkey ""ssh-rsa 1536 XX:XX:XX:XX:XX:XX:XX:XX:XX"" sftp://username/password@ipaddress" "get xxx" exit

Either way it fails with the 'Too many parameters for command 'open'' error.

The correct syntax is:
winscp.com /command "open sftp//username/password@ipaddress -hostkey=""ssh-rsa 1536 XX:XX:XX:XX:XX:XX:XX:XX:XX""" "get xxx" exit

Note the =

See https://winscp.net/eng/docs/scriptcommand_open#examples