Hi

I have Exchange 2010 and 2013 co-existance and on the 2013 server I'm getting an event id 1025 every 5 minutes saying:

SMTP rejected a (P1) mail from 'HealthMailbox21b2b04b53c34b6fae8a64de76ebb6d7@domain.local' with 'Client Proxy SRVEXCHANGE01' connector and the user authenticated as 'HealthMailbox21b2b04b53c34b6fae8a64de76ebb6d7'. The Active Directory lookup for the sender address returned validation errors. Microsoft.Exchange.Data.ProviderError

I have deleted the health mailbox account on ADUC and restarted the Exchange health service. The accounts are recreated but I still get the same error. The UPN is correct as it is using the internal domain name and the account exists on the "Monitoring Mailboxes" OU. 

I also get another error regarding a monitoring mailbox on "Microsoft->Exchange->ManagedAvailablity->Monitoring":

System.ApplicationException: monitoring mailbox HealthMailbox579c83137cc4455ba58139de9b4fb539@domain.local not found!

Any ideas?

• Edited by Antuanfff Tuesday, March 17, 2015 2:31 PM

Hi,

From your description, I would like to verify if the above event occurs when sending a message. In your case, please make sure that the Exchange server that logged this event can communicate with one or more AD servers available in your organization at first.

Here is a helpful thread for your reference:

Event id 1025

https://social.technet.microsoft.com/forums/exchange/en-US/3d2ed2ee-a8a5-4011-bb0e-f3279bb11d85/event-id-1025

Hope this can be helpful to you.

Best regards,

Hi,

Thank you for your answer but this is related to health or monitoring mailboxes, it has nothing to do with the thread you posted. 

The event occurs exactly every 5 minutes. 

I have several test users on the Exchange 2013 mailbox database and everything is working fine. But I don't want to migrate all the users before I get rid of all the error messages on the event viewer.

Hi,

In your case, I recommend you check if your Exchange server can communicate with one or more AD servers available in your organization at first. What's more, please run the Get-HealthReport -Identity xxx cmdlet to check if the AlertValue is Health.

Hope it can be helpful.

Best regards,

I did run get-healthreport. I opened another post as I'm not sure if both problems are related:

https://social.technet.microsoft.com/Forums/windowsserver/en-US/81bc6558-dbe2-433f-9eea-9d3f172925d4/onpremisessmtpclientsubmissionmonitor-unhealthy?forum=exchangesvradmin

I have several unehalthy healthsets but the only one applicable es "FrontEndTransport" where I get OnPremisesSmtpClientSubmissionMonitor unhealthy.