Mailbox Move onPrem EX2019 to EXO doesn't work - EWS problem

Question

When we try to migrate a onprem mailbox to exo we get an error in the migration batch:

The call to 'https://<ServerName>/EWS/mrsproxy.svc' failed. Error details: The HTTP request was forbidden with client authentication scheme 'Negotiate'. --> The remote server returned an error: (403) Forbidden.. --> The HTTP request was forbidden with client authentication scheme 'Negotiate'. --> The remote server returned an error: (403) Forbidden.

We check with HealthChecker.ps1 -> all OK:

[...]

MRS Proxy Enabled: True

Keep MRS Proxy disabled if you do not plan to move mailboxes cross-forest or remote

[...]

Name ExtendedProtection SslFlags IPFilteringEnabled URLRewrite Authentication

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Default Web Site/EWS Allow True (128-bit) False Windows (Negotiate,NTLM) & anonymous (default setting)

[...]

In the Windows Application Eventlog I saw this:

Exception information: 

    Exception type: HttpException 

    Exception message: MRS proxy service is disabled

   bei Microsoft.Exchange.HttpProxy.MrsProxyRequestHandler.IsMrsRequest(HttpRequest request)

   bei Microsoft.Exchange.HttpProxy.ProxyModule.SelectHandlerForAuthenticatedRequest(HttpContext httpContext)

   bei Microsoft.Exchange.HttpProxy.ProxyModule.OnPostAuthorizeInternal(HttpApplication httpApplication)

   bei Microsoft.Exchange.HttpProxy.ProxyModule.<>c__DisplayClass21_0.<OnPostAuthorizeRequest>b__0()

   bei Microsoft.Exchange.Common.IL.ILUtil.DoTryFilterCatch(Action tryDelegate, Func2 filterDelegate, Action1 catchDelegate)

   bei System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()

   bei System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)

   bei System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

I reenabled the MRSProxy by this commands without success:

Set-WebServicesVirtualDirectory "<ServerName>\EWS (Default Web Site)" -MRSProxyEnabled $false

Set-WebServicesVirtualDirectory "<ServerName>\EWS (Default Web Site)" -MRSProxyEnabled $true

I am running the HCW in newest version without errors.

Is there an another hint, who I can try???

Answer 1

Hi @Schwandtner Roland

Have you enabled basic authentication on the EWS virtual directory?

If not please enable it and see if it can help with this issue.

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