Back in 2013 Microsoft discovered a bug in the upgrade process from Microsoft System Center 2012 Orchestrator to Microsoft System Center 2012 R2 Orchestrator. More information can be found here.
This exact same problem can occur when Update Rollup 1 is applied to Microsoft System Center 2016 Orchestrator.
The web console displays this warning:
Error Executing the current operation
[httpwebrequest_webexception_remoteserver]
Arguments: NotFound
Running the following two SQL statements against the Orchestrator database will fix it:
WARNING – Run these statements at your own risk. Take all precautionary measures necessary!
GRANT EXECUTE ON object::[Microsoft.SystemCenter.Orchestrator].[GetSecurityToken] TO [Microsoft.SystemCenter.Orchestrator.Operators] GRANT SELECT ON object::[Microsoft.SystemCenter.Orchestrator.Internal].[Settings] TO [Microsoft.SystemCenter.Orchestrator.Operators]
The Automation Guy 