Exchange 2016 Event ID 1025 MSExchangeTransport / SMTP rejected a (P1) mail from Healthmailboxae

Exchange 2016 Event ID 1025 MSExchangeTransport / SMTP rejected a (P1) mail from Healthmailboxae

Again and again I see the error 1025 MSExchangeTransport with Exchange servers, which initially has no major effect. The error is part of the active HealthMonitoring of the Exchange server. The server tries to test the presence of mailboxes and other processes. For this reason, the so-called HealthMailboxes are created during installation. There is a short and good article in the technet LINK

First I tried to make the HealtMailbox completely new. This worked so far, but the error was the same. For instructions, see here

You can open the Exchange Mangement Shell to view the current healhmailboxes.

Get-Mailbox -Monitoring | ft -Wrap

First, only the names of the Healhmailboxes are shown here.

By default, the healthmailboxes in the AD are under “domain / Microsoft Exchange System Objects / Monitoring Mailboxes” (only visible in the extended view of the AD “View -> Extended features”)

This can also be found via the Powershell, if these were moved.

Get-Mailbox -Monitoring | fl DisplayName,ServerName,EmailAddresses,Database,OrganizationalUnit

Next, I searched the mailbox from the error message in ActiveDirectory.

Now look for the attribute “ProxyAddressess” in the attribute editor. There should be a SIP address and an SMTP address. After checking, I  found that the SMTP address is different than expected in the error message (.de was listed and .local the server tried to reach).

For this reason I added the “missing” SMTP address

SMTP:HealthMailboxae155….domain.local

During the next health tests approx. 5 minutes later, the error message did not show up again. Even after a few days, this error message disappeared in the event log. I suspect that this behavior is caused by an emailaddresspolicy (when applied to all mailboxes). In the background, the e-mail address policy probably tamper with the healthmailboxes, but does not enter the additional e-mail address for the healthmailboxes.

I will continue to keep this in mind, as I sometimes discover this error on customers site.

Please feel free to comment this post.

At least, the error does not restrict productivity, which can be regarded as harmless.

Have fun.