Today I tried to setup a ssh tunnel on Windows as a service. The command ran successfully in the command window, but failed every time I tried to start it as a service. Then I configured the service to run under my domain account and everything worked fine.

Apparently there's something special about running it under the local system account. I looked up the Runas command but it supported only running as another user, not as local system. I searched and found this article which solved my problem. The following captures the technique used.

Note that the spaces after binpath= and type= are required. The start service command at the end starts a cmd window using local system privileges.