ISerializable type ‘System.Net.Http.HttpRequestException’ does not have a valid constructor

[V_R]

I am using Start Job activity to run the job in community orchestrator.
And the following error appears:

An error has occured

Source: Newtonsoft.Json

Message: ISerializable type ‘System.Net.Http.HttpRequestException’ does not have a valid constructor. To correctly implement ISerializable a constructor that takes SerializationInfo and StreamingContext parameters should be present. Path ‘Error’, line 1, position 2759.

Exception Type: JsonSerializationException

Newtonsoft.Json.JsonSerializationException: ISerializable type ‘System.Net.Http.HttpRequestException’ does not have a valid constructor. To correctly implement ISerializable a constructor that takes SerializationInfo and StreamingContext parameters should be present. Path ‘Error’, line 1, position 2759.
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateISerializable(JsonReader reader, JsonISerializableContract contract, JsonProperty member, String id)
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateObject(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInternal(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.SetPropertyValue(JsonProperty property, JsonConverter propertyConverter, JsonContainerContract containerContract, JsonProperty containerProperty, JsonReader reader, Object target)
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateObject(Object newObject, JsonReader reader, JsonObjectContract contract, JsonProperty member, String id)
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateObject(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInternal(JsonReader reader, Type objectType, JsonContract contract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerMember, Object existingValue)
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)
at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType)
at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, JsonSerializerSettings settings)
at Newtonsoft.Json.JsonConvert.DeserializeObject[T](String value, JsonSerializerSettings settings)
at UiPath.Shared.JsonParser.DeserializeObject[T](String jsonValue)
at UiPath.Models.UiPathDuplexProxy.<>c__DisplayClass18_0.b__0()
at System.Threading.Tasks.Task.InnerInvoke()
at System.Threading.Tasks.Task.Execute()

Studio version: 2018.2.6 (and cannot be updated)
UiPath.Web.Activities package is updated to the latest version

The same error appears when using activities for Orchestrator HTTP requests

[andrzej.kniola (Andrzej Knioła)]

Check the Output pane or log file - whenever you see this error it is not the real error, but an error in getting the error…
The real issue should be there, just not in the error popup.

[V_R]

You are right Andrzey the real error message was somewhere else and this place was Event Viewer.
The error was:

System.Net.WebException: The remote server returned an error: (407) Proxy Authentication Required at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult) at System.Net.Http.HttpClientHandler.GetResponseCallback(IAsyncResult ar)

Which actually led me to run robot from another Internet connection. And yeah, the problem was actually in my office WiFi. It somehow blocked my requests.