ERROR with HTTP-REST : "Unable to perform operation 'find('RESTOperation',......)' on plugin 'REST' : java.lang.IllegalArgumentException: The validated string is empty"

Hello,

I am using vRO7.0 and HTTP-REST 2.0.0 plug-in at my end. I am able to execute 'Add a REST host', 'Add a REST operation' and 'Invoke a REST operation' successfully at my end.

But when I execute a customworkflow and trying to perform a GET operation, I am getting the below error.

It seems that something happened to the plug-in. Can you please help me out ?

Cannot convert to object , reason : Unable to perform operation 'find('RESTOperation', '31207c95-073c-4a9c-a2b8-bbcf94915237:5e66b54c-8624-4478-838c-b47d08651c5e')' on plugin 'REST' : java.lang.IllegalArgumentException: The validated string is empty.

Thanks,

Koushik