Not able to add a REST host in vCO 5.1 using HTTP-REST plugin

HI,

I have installed HTTP-REST 1.0.1 plugin in vCO 5.1

I am trying to configure it and add a REST host. I have imported the SSL certifcate from the REST host into my vCO server.

But the workflow is failing with error - "Workflow:Manage SSL certificates / Get URL certificates (item0)#6"

Can you please let me know what is missing and how to resolve this error?

Thanks,

Tej