SuperOffice Migration tools stops on this error

Hello, I'm doing SuperOffice Online migration for a customer, details below,

The process starts, then halts and SoMigrationToOnline log file has this error

Info Migration 2020-10-29 12:27:13.030 1 Starting migration
Info Migration 2020-10-29 12:27:13.045 9 Starting migration session(VEM motors Finland Oy, 1501045247, SuperOffice80, FI, 1, Marjut Vainio, marjut.vainio@vem.fi, 207 613 715)
Info Migration 2020-10-29 12:27:15.647 9 Documents will be uploaded to Azure Blob Storage
Info Migration 2020-10-29 12:27:15.654 9 Setup logging to Azure blob: omt\SoMigrationToOnline-2.log
Error Migration 2020-10-29 12:27:41.332 1 StorageException: An error occurred while sending the request.

StackTrace:
at Microsoft.Azure.Storage.Core.Executor.Executor.<ExecuteAsync>d__1`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.Azure.Storage.Core.Executor.Executor.<>c__DisplayClass0_0`1.<ExecuteSync>b__0()
at Microsoft.Azure.Storage.Core.Util.CommonUtility.RunWithoutSynchronizationContext[T](Func`1 actionToRun)
at Microsoft.Azure.Storage.Core.Executor.Executor.ExecuteSync[T](RESTCommand`1 cmd, IRetryPolicy policy, OperationContext operationContext)
at SuperOffice.Online.Migration.Helpers.LogHelper.InitAzure(String sas, String blobName)
at SuperOffice.Online.Migration.MigrationWorkers.StartMigrationWorker.<.ctor>b__0_0(Object sender, DoWorkEventArgs args)
at System.ComponentModel.DoWorkEventHandler.Invoke(Object sender, DoWorkEventArgs e)
at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e)
at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)
---

HttpRequestException: An error occurred while sending the request.

StackTrace:
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.Azure.Storage.Core.Executor.Executor.<ExecuteAsync>d__1`1.MoveNext()
---

WebException: The remote server returned an error: (407) Proxy Authentication Required.

StackTrace:
at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
at System.Net.Http.HttpClientHandler.GetResponseCallback(IAsyncResult ar)
---

All of the customers internet access goes through a proxy server. How this can be fixed? 

Ingen svar så langt