The error below occurs when running the robot through Management Console and prevents the robot execution to be completed,
Error from the Call REST Web Service action. Error calling REST web service. 500 loading from http://<MC URL>:<port>/ManagementConsole/rest/run/<project>/<robot name>
Cause & Solution
1. Related to number of concurrent robots in the license (CRE)
Error 500 can occur in this case when running a robot in Management Console (MC) that performs a Call REST Web Service step another robot from the same MC while the license on this MC only has one CRE available.
When a robot attempts to execute a CallREST to call another robot, it will attempt to start this second robot and will require an additional CRE license.
Resolution is this case is to assign more CRE license to the Cluster or make sure that there's at least two available.
2. Related to the robot input
Error 500 will occur if the robot input supplied by the REST client is not correct (this can happen both to the REST client being another robot using a Call REST Web service step on a third party REST client).
Resolution: verify the input needed in the robot by going to the Management Console > Repository > Robots and click the icon in the REST column of the robot.
Level of Complexity