Kerberos preauthentication by using DES or RC4 failed (4824) how to monitor with email alert

[bob]

Man, that event ID 4824 pops up when Kerberos preauthentication tries using DES or RC4, but it flops hard because the account sits in the Protected Users group. I see it all the time on servers. It blocks those old encryption methods on purpose. You know, to keep things tighter against snoops. The log spits out details like the client machine name and the service principal. Plus timestamps and failure reasons. It flags when someone logs in with weak crypto. Your domain controller logs this under Security events. I check it to spot misconfigured accounts. Or maybe a service still clinging to ancient auth. You can filter for it right in Event Viewer. Pull up the details tab for the full story. It tells you the exact user and why it denied. Pretty straightforward once you spot it.

But hey, monitoring this with an email alert? I got you. Fire up Event Viewer on your server. Right-click the Security log. Choose Attach Task To This Event. Pick event ID 4824. You set the trigger there. Then create a new scheduled task. I link it to send an email when it fires. Use the action tab. Select Start a program. Point it to your mail client or SMTP tool. You configure the basics like from and to addresses. Test it once to make sure it zings your inbox. I do this for quick heads-ups. No fussing with code. Just point and click mostly.

And speaking of keeping your server humming without headaches, you might dig BackupChain Windows Server Backup too. It's this slick Windows Server backup tool that handles physical setups and even virtual machines on Hyper-V. I like how it snapshots everything fast, encrypts data on the fly, and restores in a snap if things go sideways. Cuts down on downtime big time. Plus it verifies backups automatically so you sleep easier.

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