Hello all,

I have installed (and licensed) Umbraco Forms 8.4.0 on Umbraco 8.5.5.

After creating a form and submitting it, Umbraco throws the following exception:

Unable to cast object of type 'Umbraco.Core.Persistence.FaultHandling.RetryDbConnection' to type 'System.Data.SqlClient.SqlConnection'.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.InvalidCastException: Unable to cast object of type 'Umbraco.Core.Persistence.FaultHandling.RetryDbConnection' to type 'System.Data.SqlClient.SqlConnection'.

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace: 


[InvalidCastException: Unable to cast object of type 'Umbraco.Core.Persistence.FaultHandling.RetryDbConnection' to type 'System.Data.SqlClient.SqlConnection'.]
   NPoco.<>c.<.cctor>b__7_0(DbConnection dbConn) +32
   NPoco.SqlBulkCopyHelper.BulkInsert(IDatabase db, IEnumerable`1 list, SqlBulkCopyOptions sqlBulkCopyOptions) +112
   NPoco.Database.InsertBulk(IEnumerable`1 pocos) +171
   Umbraco.Forms.Core.Data.Storage.RecordFieldStorage.InsertRecordFields(IEnumerable`1 recordFields) +885
   Umbraco.Forms.Core.Data.Storage.RecordStorage.InsertRecord(Record record, Form form) +1833
   Umbraco.Forms.Core.Services.RecordService.StoreRecord(Record record, Form form) +1185
   Umbraco.Forms.Core.Services.RecordService.Approve(Record record, Form form) +477
   Umbraco.Forms.Core.Services.RecordService.Submit(Record record, Form form) +1167
   Umbraco.Forms.Web.Controllers.UmbracoFormsController.SubmitForm(Form form, FormViewModel model, Dictionary`2 state, ControllerContext context) +3034
   Umbraco.Forms.Web.Controllers.UmbracoFormsController.GoForward(Form form, FormViewModel model, Dictionary`2 state) +261
   Umbraco.Forms.Web.Controllers.UmbracoFormsController.HandleForm(FormViewModel model) +1261
   lambda_method(Closure , ControllerBase , Object[] ) +139
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +35
   System.Web.Mvc.Async.<>c.<BeginInvokeSynchronousActionMethod>b__9_0(IAsyncResult asyncResult, ActionInvocation innerInvokeState) +39
   System.Web.Mvc.Async.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) +77
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.<>c__DisplayClass11_0.<InvokeActionMethodFilterAsynchronouslyRecursive>b__0() +80
   System.Web.Mvc.Async.<>c__DisplayClass11_2.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2() +396
   System.Web.Mvc.Async.<>c__DisplayClass11_2.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2() +396
   System.Web.Mvc.Async.<>c__DisplayClass11_2.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2() +396
   System.Web.Mvc.Async.<>c__DisplayClass11_2.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2() +396
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.<>c__DisplayClass3_6.<BeginInvokeAction>b__4() +50
   System.Web.Mvc.Async.<>c__DisplayClass3_1.<BeginInvokeAction>b__1(IAsyncResult asyncResult) +188
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c.<BeginExecuteCore>b__152_1(IAsyncResult asyncResult, ExecuteCoreState innerState) +29
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +73
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +52
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +39
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c.<BeginProcessRequest>b__20_1(IAsyncResult asyncResult, ProcessRequestState innerState) +43
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +73
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +38
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +651
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +220
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +134

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.8.4110.0

The form is the default "Contact form" that Umbraco forms let you use as sample.

Any idea how to fix this? Thanks