Hello community,
today when finishing a proyect an unexpected error appears in my “main.xaml” file of the project:
System.NullReferenceException: Object reference not set to an instance of an object.
at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.<>c.b__19_0(HtmlValueMappingBase x)
at System.Linq.Enumerable.SelectListIterator2.MoveNext() at System.Collections.Generic.List1…ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
at UiPath.Shared.Activities.ActivityArgumentHelper.AddMultipleNonGenericArgumentsToMetadata[T](IEnumerable1 argumentList, NativeActivityMetadata metadata, String argumentPrefix) at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.CacheMetadata(NativeActivityMetadata metadata) at UiPath.Mail.Activities.Business.CreateHtmlContent.CacheMetadata(NativeActivityMetadata metadata) at System.Activities.NativeActivity.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.Validation.ActivityValidationServices.InternalActivityValidationServices.InternalValidate()
at System.Activities.Presentation.Validation.ValidationService.CoreValidationWork(ValidationReason reason, CancellationToken cancellationToken)
System.NullReferenceException: Object reference not set to an instance of an object.
at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.<>c.b__19_0(HtmlValueMappingBase x)
at System.Linq.Enumerable.SelectListIterator2.MoveNext() at System.Collections.Generic.List1…ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
at UiPath.Shared.Activities.ActivityArgumentHelper.AddMultipleNonGenericArgumentsToMetadata[T](IEnumerable1 argumentList, NativeActivityMetadata metadata, String argumentPrefix) at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.CacheMetadata(NativeActivityMetadata metadata) at UiPath.Mail.Activities.Business.CreateHtmlContent.CacheMetadata(NativeActivityMetadata metadata) at System.Activities.NativeActivity.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.Validation.ActivityValidationServices.InternalActivityValidationServices.InternalValidate()
at System.Activities.Presentation.Validation.ValidationService.CoreValidationWork(ValidationReason reason, CancellationToken cancellationToken)
System.NullReferenceException: Object reference not set to an instance of an object.
at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.<>c.b__19_0(HtmlValueMappingBase x)
at System.Linq.Enumerable.SelectListIterator2.MoveNext() at System.Collections.Generic.List1…ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
at UiPath.Shared.Activities.ActivityArgumentHelper.AddMultipleNonGenericArgumentsToMetadata[T](IEnumerable1 argumentList, NativeActivityMetadata metadata, String argumentPrefix) at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.CacheMetadata(NativeActivityMetadata metadata) at UiPath.Mail.Activities.Business.CreateHtmlContent.CacheMetadata(NativeActivityMetadata metadata) at System.Activities.NativeActivity.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.Validation.ActivityValidationServices.InternalActivityValidationServices.InternalValidate()
at System.Activities.Presentation.Validation.ValidationService.CoreValidationWork(ValidationReason reason, CancellationToken cancellationToken)
System.NullReferenceException: Object reference not set to an instance of an object.
at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.<>c.b__19_0(HtmlValueMappingBase x)
at System.Linq.Enumerable.SelectListIterator2.MoveNext() at System.Collections.Generic.List1…ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
at UiPath.Shared.Activities.ActivityArgumentHelper.AddMultipleNonGenericArgumentsToMetadata[T](IEnumerable1 argumentList, NativeActivityMetadata metadata, String argumentPrefix) at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.CacheMetadata(NativeActivityMetadata metadata) at UiPath.Mail.Activities.Business.CreateHtmlContent.CacheMetadata(NativeActivityMetadata metadata) at System.Activities.NativeActivity.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.Validation.ActivityValidationServices.InternalActivityValidationServices.InternalValidate()
at System.Activities.Presentation.Validation.ValidationService.CoreValidationWork(ValidationReason reason, CancellationToken cancellationToken)
System.NullReferenceException: Object reference not set to an instance of an object.
at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.<>c.b__19_0(HtmlValueMappingBase x)
at System.Linq.Enumerable.SelectListIterator2.MoveNext() at System.Collections.Generic.List1…ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
at UiPath.Shared.Activities.ActivityArgumentHelper.AddMultipleNonGenericArgumentsToMetadata[T](IEnumerable1 argumentList, NativeActivityMetadata metadata, String argumentPrefix) at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.CacheMetadata(NativeActivityMetadata metadata) at UiPath.Mail.Activities.Business.CreateHtmlContent.CacheMetadata(NativeActivityMetadata metadata) at System.Activities.NativeActivity.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.Validation.ActivityValidationServices.InternalActivityValidationServices.InternalValidate()
at System.Activities.Presentation.Validation.ValidationService.CoreValidationWork(ValidationReason reason, CancellationToken cancellationToken)
System.NullReferenceException: Object reference not set to an instance of an object.
at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.<>c.b__19_0(HtmlValueMappingBase x)
at System.Linq.Enumerable.SelectListIterator2.MoveNext() at System.Collections.Generic.List1…ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
at UiPath.Shared.Activities.ActivityArgumentHelper.AddMultipleNonGenericArgumentsToMetadata[T](IEnumerable1 argumentList, NativeActivityMetadata metadata, String argumentPrefix) at UiPath.Mail.Activities.Business.HtmlEditor.HtmlContentArgument.CacheMetadata(NativeActivityMetadata metadata) at UiPath.Mail.Activities.Business.CreateHtmlContent.CacheMetadata(NativeActivityMetadata metadata) at System.Activities.NativeActivity.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.Validation.ActivityValidationServices.InternalActivityValidationServices.InternalValidate()
at System.Activities.Presentation.Validation.ValidationService.CoreValidationWork(ValidationReason reason, CancellationToken cancellationToken)
This message appears out of nowhere and nothing helps point out what or qhere could be the actual cause.
Please advice in what i could do, i have already tried reinstalling studio and reviewing each one of the activities in the project.