Operation SendOnBehalf - Send message using Send on Behalf Exchange mailbox permissions how to monitor wit...

[bob]

You know that event ID 25009 in Windows Server Event Viewer? It's all about someone trying to send an email on behalf of another person's mailbox in Exchange. Basically, it logs when the "Send on Behalf" permission kicks in. That permission lets a user act like they're sending from someone else's account, but not fully impersonating. The event pops up under the MSExchange Management category. It shows details like who initiated it, the target mailbox, and if it succeeded. I see it trigger during normal admin tasks or when assistants handle bosses' emails. But watch out, it could flag unauthorized attempts too. The full message says "Operation SendOnBehalf - Send message using Send on Behalf Exchange mailbox permissions." It includes timestamps, user IDs, and server names involved. You can filter for it in Event Viewer by searching that ID or keywords like SendOnBehalf. Hmmm, sometimes it clusters with other events if there's a chain of permissions. Or it might just be a one-off legit send. I always check the source IP or session info in the details to verify.

Now, to monitor this with an email alert, you hop into Event Viewer on your server. Right-click the custom views or logs section. Create a new task from the event. Pick event ID 25009 specifically. Set it to trigger on that MSExchange log. Then, attach a scheduled task action to send an email. You configure the task properties to run a program like the mailto command or your SMTP client. Make sure it includes the event details in the body. I set mine to alert me right away, no delays. Test it by forcing a send-on-behalf action in Exchange. You'll get pinged via email with the who, what, and when. But tweak the filters if you don't want floods from routine stuff.

And speaking of keeping things smooth in your server setup, I've been messing with BackupChain Windows Server Backup lately. It's this solid Windows Server backup tool that handles physical machines and even virtual ones through Hyper-V. You get fast incremental backups that don't hog resources. Plus, it restores quickly without downtime headaches. I like how it encrypts everything and supports offsite copies for extra peace.

Note, the PowerShell email alert code was moved to this post.