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Hello dear community,
I am trying to solve a Power Query issue to refresh data from Azure Blob container storage. I am not able to refresh and getting the following error message.
Unexpected error: Value cannot be null.
Parameter name: str
Details:
Microsoft.Mashup.Evaluator.Interface.ErrorException: Value cannot be null.
Parameter name: str ---> System.ArgumentNullException: Value cannot be null.
Parameter name: str ---> System.ArgumentNullException: Value cannot be null.
Parameter name: str
at Microsoft.Mashup.Common.UriMethods.EscapeDataString(String str, Boolean legacyBehavior)
at Microsoft.Mashup.Engine1.Library.Uris.UriHelper.BuildQueryString(NameValueCollection queryParameters)
at Microsoft.Mashup.Engine1.Library.Uris.UriHelper.AddQueryRecord(UriBuilder uriBuilder, NameValueCollection newQueryString)
at Microsoft.Mashup.Engine1.Library.Http.HttpResourceCredentialDispatcher.UriCredentialDispatcher.Apply(ParameterizedCredential credential)
at Microsoft.Mashup.Engine1.Library.Http.HttpRequest.ApplyCredentialsToUri(Uri uri, ResourceCredentialCollection credentials)
at Microsoft.Mashup.Engine1.Library.Http.Request.CreateWebRequest(Uri uri, ResourceCredentialCollection credentials)
at Microsoft.Mashup.Engine1.Library.Http.Request.CreateResponse(ResourceCredentialCollection credentials)
at Microsoft.Mashup.Engine1.Library.Http.Request.GetResponseCore(ResourceCredentialCollection credentials)
at Microsoft.Mashup.Engine1.Library.Http.RetryPolicy.Execute[TResult](IEngineHost host, Func`1 func)
at Microsoft.Mashup.Engine1.Library.Http.Request.GetResponse(ResourceCredentialCollection credentials, RetryPolicy retryPolicy, SecurityExceptionCreator securityExceptionCreator, Boolean tokenRefreshed)
at Microsoft.Mashup.Engine1.Library.AzureBase.AzureBaseHelper.GetResponse(Request request, SecurityExceptionCreator securityExceptionCreator, Int32[] ignoredStatusCodes)
at Microsoft.Mashup.Engine1.Library.AzureBlobs.ContainerTableValue.BlobListEnumerator.LoadBlobsList(RecordValue& newQueryParameters)
at Microsoft.Mashup.Engine1.Library.AzureBlobs.ContainerTableValue.GetEnumerator()
at Microsoft.Mashup.Engine1.Language.Query.SelectRowsQuery.SelectRowsEnumerable.GetEnumerator()
at Microsoft.Mashup.Engine1.Language.Query.SkipTakeEnumerable.GetEnumerator()
at Microsoft.Mashup.Engine1.Language.Query.QueryTableValue.GetEnumerator()
at Microsoft.Mashup.Engine1.Runtime.TableValue.Microsoft.Mashup.Engine.Interface.ITableValue.GetEnumerator()
at Microsoft.Mashup.Evaluator.SimpleDocumentEvaluator.ValuePreviewValueSource.TableValuePreviewValueSource.SerializeRows(Int32 count)
at Microsoft.Mashup.Evaluator.SimpleDocumentEvaluator.ValuePreviewValueSource.TableValuePreviewValueSource.get_SmallValue()
at Microsoft.Mashup.Evaluator.Interface.TracingPreviewValueSource.get_SmallValue()
at Microsoft.Mashup.Evaluator.RemotePreviewValueSource.<>c__DisplayClass0_0.<RunStub>b__0()
at Microsoft.Mashup.Evaluator.EvaluationHost.ReportExceptions(String entryName, IEngineHost engineHost, IMessageChannel channel, Action action)
--- End of inner exception stack trace ---
at Microsoft.Mashup.Evaluator.EvaluationHost.<>c__DisplayClass17_0.<TryReportException>b__1()
at Microsoft.Mashup.Common.SafeExceptions.IgnoreSafeExceptions(IEngineHost host, IHostTrace trace, Action action)
at Microsoft.Mashup.Evaluator.EvaluationHost.TryReportException(IHostTrace trace, IEngineHost engineHost, IMessageChannel channel, Exception exception)
at Microsoft.Mashup.Evaluator.EvaluationHost.ReportExceptions(String entryName, IEngineHost engineHost, IMessageChannel channel, Action action)
at Microsoft.Mashup.Evaluator.RemoteDocumentEvaluator.Service.<>c__DisplayClass12_1`1.<OnBeginGetResult>b__0()
at Microsoft.Mashup.Evaluator.EvaluationHost.ReportExceptions(IHostTrace trace, IEngineHost engineHost, IMessageChannel channel, Action action)
at Microsoft.Mashup.Evaluator.RemoteDocumentEvaluator.Service.OnBeginGetResult[T](IMessageChannel channel, BeginGetResultMessage message, Action`1 action)
at Microsoft.Mashup.Evaluator.RemoteDocumentEvaluator.Service.OnBeginGetPreviewValueSource(IMessageChannel channel, BeginGetPreviewValueSourceMessage message)
at Microsoft.Mashup.Evaluator.MessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.ChannelMessenger.ChannelMessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.MessageHandlers.Dispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.ChannelMessenger.OnMessageWithUnknownChannel(IMessageChannel baseChannel, MessageWithUnknownChannel messageWithUnknownChannel)
at Microsoft.Mashup.Evaluator.MessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.ChannelMessenger.ChannelMessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.MessageHandlers.Dispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.EvaluationHost.Run()
at Microsoft.Mashup.Container.EvaluationContainerMain.Run(Object args)
at Microsoft.Mashup.Evaluator.SafeThread2.<>c__DisplayClass9_0.<CreateAction>b__0(Object o)
at Microsoft.Mashup.Container.EvaluationContainerMain.SafeRun(String[] args)
at Microsoft.Mashup.Container.EvaluationContainerMain.Main(String[] args)
--- End of inner exception stack trace ---
at Microsoft.Mashup.Evaluator.EvaluationHost.OnException(IEngineHost engineHost, IMessageChannel channel, ExceptionMessage message)
at Microsoft.Mashup.Evaluator.MessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.MessageHandlers.Dispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.ChannelMessenger.ChannelMessageHandlers.TryDispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.MessageHandlers.Dispatch(IMessageChannel channel, Message message)
at Microsoft.Mashup.Evaluator.Interface.IMessageChannelExtensions.WaitFor[T](IMessageChannel channel)
at Microsoft.Mashup.Evaluator.RemotePreviewValueSource.PreviewValueSource.WaitFor(Func`1 condition, Boolean disposing)
at Microsoft.Mashup.Evaluator.RemotePreviewValueSource.PreviewValueSource.get_SmallValue()
at Microsoft.Mashup.Evaluator.Interface.TracingPreviewValueSource.get_SmallValue()
at Microsoft.Mashup.Host.Document.Analysis.PackageDocumentAnalysisInfo.PackagePartitionAnalysisInfo.SetPreviewValue(EvaluationResult2`1 result, Func`1 getStaleSince, Func`1 getSampled)
Does anybody have a similar experience and any solution for this problem?
Thank you in advance
Hi @v-cgao-msft ,
I tried the 3 options you suggested, but no response. I am getting this error message
Can you please help me
Hi @SriKandimalla ,
1. Are you refreshing the data in the Service or in the Desktop? Are there any other data sources? Please check the version of desktop and gateway.
Downloads | Microsoft Power BI
2. Are you using a built-in connector or a custom connector, check the steps.
3. Please try unchecked "Autodetect new relationships after data is loaded".
Error Message: Value cannot be null. Parameter nam...
If the problem is not resolved, please feel free to contact me. You can provide more steps and I will try to reproduce it.
Best Regards,
Gao
Community Support Team
If there is any post helps, then please consider Accept it as the solution to help the other members find it more quickly. If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!
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