Got this error while running after updating UIPath

Main.xaml: Internal constraint exception while running constraint with name ‘Constraint’ against activity of type System.Activities.Statements.Sequence with name ‘Sequence’. Exception was: System.NullReferenceException: Object reference not set to an instance of an object.
at System.Activities.WorkflowApplication.Invoke(Activity activity, IDictionary2 inputs, WorkflowInstanceExtensionManager extensions, TimeSpan timeout) at System.Activities.WorkflowInvoker.Invoke(Activity workflow, IDictionary2 inputs, TimeSpan timeout, WorkflowInstanceExtensionManager extensions)
at System.Activities.WorkflowInvoker.Invoke(Activity workflow, IDictionary2 inputs) at System.Activities.Validation.ActivityValidationServices.RunConstraints(ChildActivity childActivity, ActivityCallStack parentChain, IList1 constraints, ProcessActivityTreeOptions options, Boolean suppressGetChildrenViolations, IList`1& validationErrors)

Hello @Sami_Rajput

I have seen similar question in the morning .

Is this error happening for any particular activity?? Any invoke workflow activity in the process??


No, I haven’t invoked any thing, was working fine before the update

Did you update to the beta version from the 2022.10.3 version??


yes, i have updated yesterday

How can I go to my previous UiPath version, until this is fixed

As per my understanding you cannot roll back the changes.

For a trial Can you try lower the packages in the project and check it once.


I tried to downgrade System.activities to 22.4.5
and now got 2 similar errors :slight_smile:

The issue is with the powershell snippet. There is no workaround - the current UiPath version has broken all my workflows. How did this get through qa.

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Hi @AutumnBreeze

Did you figure it out how to solve this issue?

i have the same problem here

In my case, there was no shortcut
I had to copy paste each activity to a separate project one by one and now it’s working fine.
And once you found out which activity is causing the issue, remove it and then again use it

@Sami_Rajput - removing and readding does not necessarily fix it. If you see above, this is a new project with a new flow and exactly one statement added to invoke powershell. Nothing legacy. It failed.

At this time there is no workaround except to not use invoke powershell.

Just to share with everyone that removing all activities from the faulty workflow - as @Sami_Rajput reported - and then creating a new one from scratch and then copying the activities back one by one did the trick for me.

Curious to understand what caused the problem and if it is probe to occur again in other legacy automation projects of mine.

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