Invoke workflow: The invocation of the constructor on type 'UiPath.Callout.Activity.CallOutActivity' that matches the specified binding constraints threw an exception

Invoke workflow giving out this error:
Invoke abac workflow: The invocation of the constructor on type ‘UiPath.Callout.Activity.CallOutActivity’ that matches the specified binding constraints threw an exception.

its an attended bot and in the abac workflow am using call out messages to display certain error to the user.
Please advice.
thank you

Hi @sindhu_gururaj,

Can you share the stack trace here please? The may be an inner exception that contains the actual error encountered.

Thanks

I guess I have the same problem. Here is the error message, how to fix?
RemoteException wrapping System.Xaml.XamlObjectWriterException: The invocation of the constructor on type ‘UiPath.Callout.Activity.CallOutActivity’ that matches the specified binding constraints threw an exception. —> RemoteException wrapping System.Exception: CEF can only be initialized once per process. This is a limitation of the underlying CEF/Chromium framework. You can change many (not all) settings at runtime through RequestContext.SetPreference. See General Usage · cefsharp/CefSharp Wiki · GitHub Use Cef.IsInitialized to guard against this exception. If you are seeing this unexpectedly then you are likely calling Cef.Initialize after you’ve created an instance of ChromiumWebBrowser,
it must be before the first instance is created.
at CefSharp.Core.Cef.Initialize(CefSettingsBase cefSettings,
Boolean performDependencyCheck,
IApp cefApp)
at CefSharp.Cef.Initialize(CefSettingsBase settings,
Boolean performDependencyCheck,
IBrowserProcessHandler browserProcessHandler)
at UiPath.Callout.Helper.CefSharpHelper.InitCefSharp()
at UiPath.Callout.CalloutForm.FormView…ctor()
at UiPath.Callout.Activity.CallOutActivity.b__66_0()
at System.Windows.Threading.Dispatcher.Invoke(Action callback,
DispatcherPriority priority,
CancellationToken cancellationToken,
TimeSpan timeout)
at System.Windows.Threading.Dispatcher.Invoke(Action callback)
at UiPath.Callout.Activity.CallOutActivity.Init()
at UiPath.Callout.Activity.CallOutActivity…ctor()
— End of inner exception stack trace —
at MS.Internal.Xaml.Runtime.ClrObjectRuntime.CreateInstance(XamlType xamlType,
Object args)
at System.Xaml.XamlObjectWriter.Logic_CreateAndAssignToParentStart(ObjectWriterContext ctx)
at System.Xaml.XamlObjectWriter.WriteStartMember(XamlMember property)
at System.Xaml.XamlWriter.WriteNode(XamlReader reader)
at System.Xaml.XamlServices.Transform(XamlReader xamlReader,
XamlWriter xamlWriter,
Boolean closeWriter)
at System.Activities.XamlIntegration.FuncFactory1.Evaluate() at System.Activities.DynamicActivity.OnInternalCacheMetadata(Boolean createEmptyBindings) at System.Activities.Activity.InternalCacheMetadata(Boolean createEmptyBindings, IList1& validationErrors)
at System.Activities.ActivityUtilities.ProcessActivity(ChildActivity childActivity,
ChildActivity& nextActivity,
Stack1& activitiesRemaining, ActivityCallStack parentChain, IList1& validationErrors,
ProcessActivityTreeOptions options,
ProcessActivityCallback callback)
at System.Activities.ActivityUtilities.ProcessActivityTreeCore(ChildActivity currentActivity,
ActivityCallStack parentChain,
ProcessActivityTreeOptions options,
ProcessActivityCallback callback,
IList1& validationErrors) at System.Activities.ActivityUtilities.CacheRootMetadata(Activity activity, LocationReferenceEnvironment hostEnvironment, ProcessActivityTreeOptions options, ProcessActivityCallback callback, IList1& validationErrors)
at System.Activities.WorkflowInspectionServices.d__3.MoveNext()
at System.Linq.Enumerable.d__172.MoveNext() at System.Linq.Enumerable.<ConcatIterator>d__591.MoveNext()
at System.Linq.Enumerable.d__172.MoveNext() at System.Linq.Enumerable.WhereSelectEnumerableIterator2.MoveNext()
at System.Linq.Enumerable.d__641.MoveNext() at System.Linq.Buffer1…ctor(IEnumerable1 source) at System.Linq.Enumerable.ToArray[TSource](IEnumerable1 source)
at UiPath.Executor.Tracking.TrackingHelpers.GetVariableNames(Activity activity)
at UiPath.Executor.Tracking.TrackingHelpers.TrackVariables(TrackingProfile profile,
WorkflowInfo workflowInfo)
at UiPath.Executor.Tracking.DebugTrackingParticipant.RegisterWorkflow(WorkflowInfo workflowInfo)
at UiPath.Executor.DebuggerPlugin.UiPath.Executor.IDebuggerPlugin.RegisterWorkflowTracking(WorkflowInfo workflowInfo)
at UiPath.Executor.Tracking.WorkflowTracking.RegisterWorkflowTracking(WorkflowInfo workflowInfo)
at UiPath.Executor.WorkflowRuntime.RegisterWorkflow(WorkflowInfo workflowInfo)
at UiPath.Executor.InProcessRunner.<>c__DisplayClass6_0.g__StartWorkflow|1()
at UiPath.Executor.InProcessRunner.BeginExecute(AsyncCallback callback,
Object state)
at UiPath.Core.Activities.ExecutorInvokeActivity.BeginExecute(AsyncCodeActivityContext context,
AsyncCallback callback,
Object state)
at System.Activities.AsyncCodeActivity.InternalExecute(ActivityInstance instance,
ActivityExecutor executor,
BookmarkManager bookmarkManager)
at System.Activities.ActivityInstance.Execute(ActivityExecutor executor,
BookmarkManager bookmarkManager)
at System.Activities.Runtime.ActivityExecutor.ExecuteActivityWorkItem.ExecuteBody(ActivityExecutor executor,
BookmarkManager bookmarkManager,
Location resultLocation)

Hi @sindhu_gururaj and @kare.smorvik,

Your error message seems to be slightly different from this issue, but might be related:

Can you provide a screenshot or attach the xaml file that shows what you are attempting to accomplish?

Which dependencies are you using in your project and what versions are they?

Are you using a Create Form and a Callout in the same workflow?
If so, you may need to enable the Isolated property on the Create Form Activity.

Thanks

Thanks. I did use both form and call out and yes, when I isloated form to flow works fine.

This issue was solved. updated the uipath forms package