Microsoft has just announced some beta anti-virus/spyware/malware protection software called Microsoft Essentials. It's free and free is good.

This software is only available to people running a legal copy of Windows. This is fine. My copies of XP are all legal as is my Windows 7.

After jumping thru several hoops trying to download this thing, I sign in with my Windows Live ID (required), fill out a registration form (required), validate my email address (required), and THEN...

The red box says:

The invitation you are using belongs to another registered account. If you believe you received this message in error, please try using another Windows Live ID/Passport account or contact mchelp@microsoft.com for additional assistance.

What?

Geez, thanks Microsoft. Now I can't even try your software.

So if you want to try out Microsoft Essentials, if you can get past the registration process, you did better than me.