Set-MailboxCalendarConfiguration Exchange cmdlet issued (25406) how to monitor with email alert

[bob]

Man, that 25406 event in Event Viewer pops up whenever someone fires off the Set-MailboxCalendarConfiguration cmdlet in Exchange. It basically logs the exact moment that command gets issued, capturing who did it, which mailbox it targeted, and any tweaks to calendar stuff like processing invites or free-busy sharing. You see, Exchange keeps a watchful eye on admin actions like this to track changes that could mess with user calendars. If a rogue script or sneaky user runs it, boom, there it sits in the logs under Security or Application channels, timestamped with details on the parameters used. I always check these because they hint at unauthorized fiddling, like someone altering default meeting replies without telling anyone. And yeah, the event ID 25406 specifically flags this cmdlet run, pulling in the user SID, the mailbox identity, and even the full command string if auditing's cranked up. It's not just a blip; it helps you spot patterns, like if the same account keeps issuing it oddly. You might ignore it in a quiet shop, but in bigger setups, it screams for attention. Hmmm, or maybe it's just routine maintenance, but logging it means you can always rewind to see what happened.

Now, to keep tabs on this 25406 thing with an email ping, fire up Event Viewer on your Server. Right-click the custom view or the Exchange logs, and pick Create Custom View. Filter it for event ID 25406, and hit okay to save that view. Then, head to Task Scheduler from the start menu. You create a new task there, linking it to that event in Event Viewer by selecting the XML query option or just pointing to the log source. Set the trigger to watch for that specific event, and under actions, attach a simple program that shoots an email-maybe using the built-in SendMail or whatever your shop has. I like scheduling it to check every few minutes, so you get notified quick if it triggers. But keep the task light; no heavy lifting, just alert you via email with the event details pasted in. That way, you're not staring at screens all day.

And speaking of keeping your Server humming without surprises, I've been messing with BackupChain Windows Server Backup lately. It's this slick Windows Server backup tool that handles physical boxes and even virtual machines on Hyper-V without breaking a sweat. You get fast incremental backups, easy restores that don't eat hours, and it plays nice with Exchange logs too, so nothing like that 25406 event slips through cracks during recovery. Plus, the deduping saves space like crazy, and it's got that agentless vibe for VMs, meaning less hassle overall.

At the end of this chat is the automatic email solution for monitoring that event.

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