A null key is not allowed in a hash literal.

I am automating my directories sync but when I try to connect using .Net assembly via powershell to the external SFTP site I get this: A null key is not allowed in a hash literal.
Is this because I am using IP adddress in here: $sessionOptions.HostName = "x.x.x.x"
I am using Version 5.7.6 (biild 5874)

Thank you,
T.

I assume you did not initialize the $sessionOptions variable.

Show us your complete script.