Workflow Activity "Lookup Value" returns An error occured while enumerating the filter using [//WorkflowData/customvalue]

Question

I want to generate an Accountname using EmployeeID, FirstName and LastName via a workflow.
I'm using the Granfeldt Workflow Activity Library (https://fimactivitylibrary.codeplex.com/)
I'm using the FIM Powershell Workflow Activity (https://fimpowershellwf.codeplex.com/)
Steps:
Passing the EmployeeID, FirstName and LastName to the powershell Activity, generating a logonid based on logic.
Add-PSSnapin FIMAutomation
$EmployeeID = $fimwf.WorkflowDictionary.EmployeeID
$Forename = $fimwf.WorkflowDictionary.Firstname
$Lastname = $fimwf.WorkflowDictionary.Lastname
'logic creating a custom logonid here
   ==> This works
Returning data back to the workflow via that powershell script:
$fimwf.WorkflowDictionary.Add('NewAccountName',$newlogonid)
   ==> This works
 Using Lookup Value Activity to read the Workflow data and update the [//Target/AccountName] fails.
This gives an error:
       An error occurred while enumerating the filter 'string' .
(where string is the actual generated userid that I've got back from the powershell script. Example dab2563)
I tried with only [//WorkflowData], then this gives the error:
      Index was outside the bounds of the array.
Any hints to solve this?    
Kind regards,
David

Answer 1

The Lookup Activity is for looking up an object in the FIM Service. Seems like thats not what you're trying to accomplish.
For updating the target of the workflow, just use the built-in Function Evaluator. The Lookup WF was not built for that and it is failing because you have not specified a valid XPAth lookup filter, such as /Person[AccountName='BillG']
Regards, Soren Granfeldt
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